Description of problem:
Guest will be destroyed if iscsi pool is destroyed and libvirtd restart

Version-Release number of selected component (if applicable):
libvirt-7.0.0-8.module+el8.4.0+10233+8b7fd9eb.x86_64
qemu-kvm-5.2.0-10.module+el8.4.0+10217+cbdd2152.x86_64

How reproducible:
100%

Steps to Reproduce:
1. Start a storage Regres pool with iscsi backend storage.

1. cat iscsi-pool.xml
   <pool type='iscsi'>
   <name>iscsi</name>
   <uuid>37219096-5307-4e8f-af91-c22c45420563</uuid>
   <capacity unit='bytes'>21474836480</capacity>
   <allocation unit='bytes'>21474836480</allocation>
   <available unit='bytes'>0</available>
   <source>
   <host name='*IP*' port='3260'/>
   <device path='iqn.2021-01.com.redhat:test'/>
   </source>
   <target>
   <path>/dev/disk/by-path</path>
   <permissions>
   <mode>0755</mode>
   <owner>-1</owner>
   <group>-1</group>
   </permissions>
   </target>
   </pool>
2. virsh pool-define iscsi-pool.xml
   Pool iscsi defined from iscsi-pool.xml
3. virsh pool-start iscsi
   Pool iscsi started
4. virsh pool-list --all
   Name State Autostart
   ---------------------------------
   default active yes
   iscsi active no

2. Start a domain with a disk from that storage pool

1. virsh dumpxml lmn | grep /disk -B10
   ...
   <disk type='volume' device='disk'>
   <driver name='qemu' type='raw'/>
   <source pool='iscsi' volume='unit:0:0:0' mode='host' index='1'/>
   <backingStore/>
   <target dev='vdc' bus='virtio'/>
   <alias name='virtio-disk2'/>
   <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
   </disk>
2. virsh list --all
   Id Name State
   ---------------------------------
   1 lmn running

3. Set the pool as autostart

1. virsh pool-autostart iscsi
   Pool iscsi marked as autostarted

4. Destroy the pool and restart libvirtd

1. virsh pool-destroy iscsi
   Pool iscsi destroyed
2. systemctl restart libvirtd

5. Check the guest status.

1. virsh list --all
   Id Name State
   ---------------------------------

• lmn shut off

Actual results:
Guest will be destroyed

Expected results:
Guest is still in running

Additional info:
1. Same with iscsi-direct pool.
2. libvirtd.log:
2021-03-09 09:45:33.230+0000: 324447: debug : virGetConnectGeneric:156 : Opened new storage connection 0x7f3c58015190
2021-03-09 09:45:33.230+0000: 324447: debug : virStoragePoolLookupByName:367 : conn=0x7f3c58015190, name=iscsi
2021-03-09 09:45:33.230+0000: 324447: debug : virAccessManagerCheckStoragePool:359 : manager=0x559816feedf0(name=stack) driver=storage pool=0x7f3c5810e8d0 perm=0
2021-03-09 09:45:33.230+0000: 324447: debug : virAccessManagerCheckStoragePool:359 : manager=0x559816feee50(name=none) driver=storage pool=0x7f3c5810e8d0 perm=0
2021-03-09 09:45:33.230+0000: 324447: debug : virStoragePoolIsActive:2187 : pool=0x7f3c580205f0
2021-03-09 09:45:33.230+0000: 324447: debug : virAccessManagerCheckStoragePool:359 : manager=0x559816feedf0(name=stack) driver=storage pool=0x7f3c5810e8d0 perm=1
2021-03-09 09:45:33.230+0000: 324447: debug : virAccessManagerCheckStoragePool:359 : manager=0x559816feee50(name=none) driver=storage pool=0x7f3c5810e8d0 perm=1
2021-03-09 09:45:33.230+0000: 324447: error : virDomainStorageSourceTranslateSourcePool:31401 : unsupported configuration: storage pool 'iscsi' containing volume 'unit:0:0:0' is not active
2021-03-09 09:45:33.230+0000: 324447: debug : virStoragePoolDispose:601 : release pool 0x7f3c580205f0 iscsi 37219096-5307-4e8f-af91-c22c45420563
2021-03-09 09:45:33.230+0000: 324447: debug : qemuProcessStop:7590 : Shutting down vm=0x5598170216a0 name=lmn id=2 pid=324291, reason=daemon, asyncJob=none, flags=0x0
2021-03-09 09:45:33.230+0000: 324447: debug : qemuDomainLogAppendMessage:6605 : Append log message (vm='lmn' message='2021-03-09 09:45:33.230+0000: shutting down, reason=daemon
) stdioLogD=1
2021-03-09 09:45:33.230+0000: 324447: debug : virNetSocketNewConnectUNIX:683 : path=/run/libvirt/virtlogd-sock spawnDaemon=0 binary=<null>
2021-03-09 09:45:33.230+0000: 324447: debug : virNetSocketNewConnectUNIX:739 : connect() succeeded
2021-03-09 09:45:33.230+0000: 324447: debug : virNetSocketNew:245 : localAddr=0x7f3c43ffe540 remoteAddr=0x7f3c43ffe5d0 fd=34 errfd=-1 pid=0
2021-03-09 09:45:33.230+0000: 324447: info : virNetSocketNew:301 : RPC_SOCKET_NEW: sock=0x5598170848b0 fd=34 errfd=-1 pid=0 localAddr=127.0.0.1;0, remoteAddr=127.0.0.1;0