Bug 1887482

Description of problem:
When importing from VMware to CNV in case the vddk init image is missing,
there is a warning in the VM import wizard page:

"Danger alert:Image configuration missing
The following images are missing in a v2v-vmware ConfigMap: vddk-init-image. Please see documentation for more information."

If this warning is ignored and VM import is run anyway,
it will immediately fail:
 
"Error creating virtual machine.
Error "Required value" for field "spec.initContainers[0].image".
Pod kubevirt-v2v-conversion-rhel8template- failed to create"

This last error message do not indicate at all that the problem is that vddk-init-image is missing.
 
Version-Release number of selected component (if applicable):
OCP-4.6/CNV-2.5

How reproducible:
100%

Expected results:
The error in case of VM import with no vddk-init-image should indicate that.

Additional info:
What's displayed when opening the 
"Pod kubevirt-v2v-conversion-rhel8template- failed to create"

{
 "kind": "Pod",
 "apiVersion": "v1",
 "metadata": {
  "generateName": "kubevirt-v2v-conversion-rhel8template-",
  "namespace": "default"
 },
 "spec": {
  "restartPolicy": "Never",
  "serviceAccountName": "kubevirt-v2v-conversion-22z27",
  "initContainers": [
   {
    "name": "vddk-init",
    "volumeMounts": [
     {
      "name": "volume-vddk",
      "mountPath": "/opt/vmware-vix-disklib-distrib"
     }
    ]
   }
  ],
  "containers": [
   {
    "name": "kubevirt-v2v-conversion",
    "imagePullPolicy": "IfNotPresent",
    "image": "registry.redhat.io/container-native-virtualization/kubevirt-v2v-conversion@sha256:3f713f9db2bc69b0e01ca3843d1d1170adf5864a25860e7f9ec53ea3a12153dc",
    "securityContext": {
     "privileged": true
    },
    "volumeMounts": [
     {
      "name": "configuration",
      "mountPath": "/data/input"
     },
     {
      "name": "kvm",
      "mountPath": "/dev/kvm"
     },
     {
      "name": "volume-vddk",
      "mountPath": "/opt/vmware-vix-disklib-distrib"
     },
     {
      "name": "v2v-conversion-temp",
      "mountPath": "/var/tmp"
     },
     {
      "name": "harddisk1",
      "mountPath": "/data/vm/disk1"
     }
    ],
    "volumeDevices": []
   }
  ],
  "volumes": [
   {
    "name": "configuration",
    "secret": {
     "secretName": "kubevirt-v2v-conversion-gb9bb"
    }
   },
   {
    "name": "kvm",
    "hostPath": {
     "path": "/dev/kvm"
    }
   },
   {
    "name": "volume-vddk",
    "emptyDir": {}
   },
   {
    "name": "v2v-conversion-temp",
    "emptyDir": {}
   },
   {
    "name": "harddisk1",
    "persistentVolumeClaim": {
     "claimName": "harddisk1-k2gm5"
    }
   }
  ]
 }
}