Description of problem:
Virt-v2v can't convert guest with disk mode 'independent' from VMware via vddk >= 7.0

Version-Release number of selected component (if applicable):
virt-v2v-2.3.4-1.el9.x86_64
libguestfs-1.50.1-3.el9.x86_64
guestfs-tools-1.50.1-2.el9.x86_64
nbdkit-server-1.34.0-1.el9.x86_64
libnbd-1.16.0-1.el9.x86_64
libvirt-libs-9.2.0-1.el9.x86_64
qemu-img-7.2.0-14.el9_2.x86_64

How reproducible:
100%

Steps to Reproduce:
1. Prepare a guest which has disk mode 'indepentent' on VMware, pls refer to scrreenshot 'vmware-guest-with-independent-disk-mode.png'

2. Convert the guest from VMware via vddk>=7.0 by virt-v2v
2.1 with vddk8.0.0

1. virt-v2v -ic vpx://root@10.73.212.149/data/10.73.212.36/?no_verify=1 -it vddk -io vddk-libdir=/home/vddk8.0.0 -io vddk-thumbprint=D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94 -ip /home/passwd esx8.0-rhel9.3-x86_64
   [ 0.0] Setting up the source: -i libvirt -ic vpx://root@10.73.212.149/data/10.73.212.36/?no_verify=1 -it vddk esx8.0-rhel9.3-x86_64
   [ 1.9] Opening the source
   nbdkit: vddk[1]: error: VixDiskLib_Open: [esx8.0-matrix] esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmdk: Unknown error
   nbdkit: vddk[1]: error: Please verify whether the "thumbprint" parameter (D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94) matches the SHA1 fingerprint of the remote VMware server. Refer to nbdkit-vddk-plugin(1) section "THUMBPRINTS" for details.
   nbdkit: vddk[1]: error: VixDiskLib_Open: [esx8.0-matrix] esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmdk: Unknown error
   nbdkit: vddk[1]: error: Please verify whether the "thumbprint" parameter (D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94) matches the SHA1 fingerprint of the remote VMware server. Refer to nbdkit-vddk-plugin(1) section "THUMBPRINTS" for details.
   nbdkit: vddk[1]: error: VixDiskLib_Open: [esx8.0-matrix] esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmdk: Unknown error
   nbdkit: vddk[1]: error: Please verify whether the "thumbprint" parameter (D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94) matches the SHA1 fingerprint of the remote VMware server. Refer to nbdkit-vddk-plugin(1) section "THUMBPRINTS" for details.
   nbdkit: vddk[1]: error: VixDiskLib_Open: [esx8.0-matrix] esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmdk: Unknown error
   nbdkit: vddk[1]: error: Please verify whether the "thumbprint" parameter (D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94) matches the SHA1 fingerprint of the remote VMware server. Refer to nbdkit-vddk-plugin(1) section "THUMBPRINTS" for details.
   nbdkit: vddk[1]: error: VixDiskLib_Open: [esx8.0-matrix] esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmdk: Unknown error
   nbdkit: vddk[1]: error: Please verify whether the "thumbprint" parameter (D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94) matches the SHA1 fingerprint of the remote VMware server. Refer to nbdkit-vddk-plugin(1) section "THUMBPRINTS" for details.
   nbdkit: vddk[1]: error: VixDiskLib_Open: [esx8.0-matrix] esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmdk: Unknown error
   nbdkit: vddk[1]: error: Please verify whether the "thumbprint" parameter (D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94) matches the SHA1 fingerprint of the remote VMware server. Refer to nbdkit-vddk-plugin(1) section "THUMBPRINTS" for details.
   virt-v2v: error: libguestfs error: could not create appliance through
   libvirt.

Try running qemu directly without libvirt using this environment variable:
export LIBGUESTFS_BACKEND=direct

Original error from libvirt: internal error: process exited while
connecting to monitor: 2023-04-21T10:07:03.922622Z qemu-kvm: -blockdev
{"driver":"nbd","server":

{"type":"unix","path":"/tmp/v2v.zxZ5Sg/in0"}

,"node-name":"libvirt-2-storage","cache":

{"direct":false,"no-flush":true}

,"auto-read-only":true,"discard":"unmap"}:
Requested export not available [code=1 int1=-1]

If reporting bugs, run virt-v2v with debugging enabled and include the
complete output:

virt-v2v -v -x [...]

2.2 with vddk7.0

1. virt-v2v -ic vpx://root@10.73.212.149/data/10.73.212.36/?no_verify=1 -it vddk -io vddk-libdir=/home/vddk7.0 -io vddk-thumbprint=D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94 -ip /home/passwd esx8.0-rhel9.3-x86_64
   [ 0.0] Setting up the source: -i libvirt -ic vpx://root@10.73.212.149/data/10.73.212.36/?no_verify=1 -it vddk esx8.0-rhel9.3-x86_64
   [ 1.9] Opening the source
   nbdkit: vddk[1]: error: VixDiskLib_Open: [esx8.0-matrix] esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmdk: Unknown error
   nbdkit: vddk[1]: error: Please verify whether the "thumbprint" parameter (D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94) matches the SHA1 fingerprint of the remote VMware server. Refer to nbdkit-vddk-plugin(1) section "THUMBPRINTS" for details.
   nbdkit: vddk[1]: error: VixDiskLib_Open: [esx8.0-matrix] esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmdk: Unknown error
   nbdkit: vddk[1]: error: Please verify whether the "thumbprint" parameter (D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94) matches the SHA1 fingerprint of the remote VMware server. Refer to nbdkit-vddk-plugin(1) section "THUMBPRINTS" for details.
   nbdkit: vddk[1]: error: VixDiskLib_Open: [esx8.0-matrix] esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmdk: Unknown error
   nbdkit: vddk[1]: error: Please verify whether the "thumbprint" parameter (D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94) matches the SHA1 fingerprint of the remote VMware server. Refer to nbdkit-vddk-plugin(1) section "THUMBPRINTS" for details.
   nbdkit: vddk[1]: error: VixDiskLib_Open: [esx8.0-matrix] esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmdk: Unknown error
   nbdkit: vddk[1]: error: Please verify whether the "thumbprint" parameter (D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94) matches the SHA1 fingerprint of the remote VMware server. Refer to nbdkit-vddk-plugin(1) section "THUMBPRINTS" for details.
   nbdkit: vddk[1]: error: VixDiskLib_Open: [esx8.0-matrix] esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmdk: Unknown error
   nbdkit: vddk[1]: error: Please verify whether the "thumbprint" parameter (D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94) matches the SHA1 fingerprint of the remote VMware server. Refer to nbdkit-vddk-plugin(1) section "THUMBPRINTS" for details.
   nbdkit: vddk[1]: error: VixDiskLib_Open: [esx8.0-matrix] esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmdk: Unknown error
   nbdkit: vddk[1]: error: Please verify whether the "thumbprint" parameter (D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94) matches the SHA1 fingerprint of the remote VMware server. Refer to nbdkit-vddk-plugin(1) section "THUMBPRINTS" for details.
   virt-v2v: error: libguestfs error: could not create appliance through
   libvirt.

Try running qemu directly without libvirt using this environment variable:
export LIBGUESTFS_BACKEND=direct

Original error from libvirt: internal error: process exited while
connecting to monitor: 2023-04-21T11:36:37.840542Z qemu-kvm: -blockdev
{"driver":"nbd","server":

{"type":"unix","path":"/tmp/v2v.WwjOCy/in0"}

,"node-name":"libvirt-2-storage","cache":

{"direct":false,"no-flush":true}

,"auto-read-only":true,"discard":"unmap"}:
Requested export not available [code=1 int1=-1]

If reporting bugs, run virt-v2v with debugging enabled and include the
complete output:

virt-v2v -v -x [...]

Actual results:
As above description

Expected results:
Maybe the bug is caused by vddk library, v2v can improve the error or something

Additional info:
1. Can Convert the guest from VMware via vddk<7.0 by virt-v2v
1.1 # virt-v2v -ic vpx://root@10.73.212.149/data/10.73.212.36/?no_verify=1 -it vddk -io vddk-libdir=/home/vddk6.7 -io vddk-thumbprint=D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94 -ip /home/passwd esx8.0-rhel9.3-x86_64
[ 0.0] Setting up the source: -i libvirt -ic vpx://root@10.73.212.149/data/10.73.212.36/?no_verify=1 -it vddk esx8.0-rhel9.3-x86_64
[ 1.8] Opening the source
[ 10.1] Inspecting the source
[ 22.7] Checking for sufficient free disk space in the guest
[ 22.7] Converting Red Hat Enterprise Linux 9.3 Beta (Plow) to run on KVM
^Cvirt-v2v: Exiting on signal SIGINT

1.2 # virt-v2v -ic vpx://root@10.73.212.149/data/10.73.212.36/?no_verify=1 -it vddk -io vddk-libdir=/home/vddk6.5 -io vddk-thumbprint=D1:03:96:7E:11:3D:7C:4C:B6:50:28:1B:63:74:B5:40:5F:9D:9F:94 -ip /home/passwd esx8.0-rhel9.3-x86_64
[ 0.9] Setting up the source: -i libvirt -ic vpx://root@10.73.212.149/data/10.73.212.36/?no_verify=1 -it vddk esx8.0-rhel9.3-x86_64
[ 2.7] Opening the source
[ 13.9] Inspecting the source
[ 26.6] Checking for sufficient free disk space in the guest
[ 26.6] Converting Red Hat Enterprise Linux 9.3 Beta (Plow) to run on KVM
^Cvirt-v2v: Exiting on signal SIGINT

2. Can convert the guest from VMware without vddk by virt-v2v

1. virt-v2v -ic vpx://root@10.73.212.149/data/10.73.212.36/?no_verify=1 -ip /home/passwd esx8.0-rhel9.3-x86_64[ 0.0] Setting up the source: -i libvirt -ic vpx://root@10.73.212.149/data/10.73.212.36/?no_verify=1 esx8.0-rhel9.3-x86_64
   [ 2.5] Opening the source
   [ 37.5] Inspecting the source
   [ 795.6] Checking for sufficient free disk space in the guest
   [ 795.6] Converting Red Hat Enterprise Linux 9.3 Beta (Plow) to run on KVM
   ^Cvirt-v2v: Exiting on signal SIGINT

3. Can convert the guest from VMware via vmx+ssh by virt-v2v

1. virt-v2v -i vmx -it ssh ssh://root@10.73.212.36/vmfs/volumes/esx8.0-matrix/esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmx -ip /home/esxpwd
   [ 0.0] Setting up the source: -i vmx ssh://root@10.73.212.36/vmfs/volumes/esx8.0-matrix/esx8.0-rhel9.3-x86_64_1/esx8.0-rhel9.3-x86_64.vmx
   The authenticity of host '10.73.212.36 (10.73.212.36)' can't be established.
   ECDSA key fingerprint is SHA256:kV9S4wQ7Amf6K+Gfkl8MeLKsPZ2OyS/3dfQq0TEMONc.
   This key is not known by any other names
   Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
   (root@10.73.212.36) Password:
   (root@10.73.212.36) Password:
   (root@10.73.212.36) Password:
   (root@10.73.212.36) Password:
   [ 41.1] Opening the source
   [ 46.4] Inspecting the source
   [ 57.5] Checking for sufficient free disk space in the guest
   [ 57.5] Converting Red Hat Enterprise Linux 9.3 Beta (Plow) to run on KVM
   ^Cvirt-v2v: Exiting on signal SIGINT