Azure IPI creates boot images using the image gallery API now, it will create two image definition resources for both hyperVGeneration V1 and V2. For arm64 cluster, the architecture in image definition hyperVGeneration V1 is x64, but it should be Arm64

./openshift-install version
./openshift-install 4.12.0-0.nightly-arm64-2022-10-07-204251
built from commit 7b739cde1e0239c77fabf7622e15025d32fc272c
release image registry.ci.openshift.org/ocp-arm64/release-arm64@sha256:d2569be4ba276d6474aea016536afbad1ce2e827b3c71ab47010617a537a8b11
release architecture arm64

always

1.Create arm cluster using latest arm64 nightly build 
2.Check image definition created for hyperVGeneration V1

The architecture field is x64.
###
$ az sig image-definition show --gallery-name ${gallery_name} --gallery-image-definition lwanazarm1008-rc8wh --resource-group ${rg} | jq -r ".architecture"
x64
The image version under this image definition is for aarch64.
###
$ az sig image-version show --gallery-name gallery_lwanazarm1008_rc8wh --gallery-image-definition lwanazarm1008-rc8wh --resource-group lwanazarm1008-rc8wh-rg --gallery-image-version 412.86.20220922 | jq -r ".storageProfile.osDiskImage.source"
{  "uri": "https://clustermuygq.blob.core.windows.net/vhd/rhcosmuygq.vhd"}
$ az storage blob show --container-name vhd --name rhcosmuygq.vhd --account-name clustermuygq --account-key $account_key | jq -r ".metadata"
{  "Source_uri": "https://rhcos.blob.core.windows.net/imagebucket/rhcos-412.86.202209220538-0-azure.aarch64.vhd"}

Although no VMs with HypergenV1 can be provisioned, the architecture field should be Arm64 even for hyperGenerationV1 image definitions

1.The architecture in image definition hyperVGeneration V2 is Arm64 and installer will use V2 by default for arm64 vm_type, so installation didn't fail by default. But we still need to make architecture consistent in V1.

2.Need to set architecture field for both V1 and V2, now we only set architecture in V2 image definition resource. 
https://github.com/openshift/installer/blob/master/data/data/azure/vnet/main.tf#L100-L128