Description of problem:
Currently we don't have validating webhook for `virtualMachineMigrationResourceQuota` CR, so it is possible to set anything under `additionalMigrationResources` field:

$ oc get vmmrq my-vmmrq -o json | jq .spec
{
"additionalMigrationResources":

}

Probably, VMMRQ should support only those resources that are associated with VM migrations, e.g.: cpu, memory, number of pods..

Version-Release number of selected component (if applicable):
4.14