1. Proposed title of this feature request: oc-mirror to mirror also the RHCOS image for HyperShift KubeVirt provider when mirroring the OCP release payload

2. What is the nature and description of the request?
When using the KubeVirt (OpenShift Virtualization) provider for HyperShift, the KubeVirt VMs that are going to serve as nodes for the hosted clusters will consume an RHOCS image shipped as a container-disk image for KubeVirt.
So, in order to have it working also on disconnected/air-gapped environments that image should also be part of the mirroring process.
When mirroring an OCP release image, oc-mirror currently processes only the images directly referenced in release-manifests/image-references file in the release payload image.
The RHCOS image for HyperShift KubeVirt provider is referenced in release-manifests/0000_50_installer_coreos-bootimages.yaml but not in release-manifests/image-references in the OCP release image and so oc-mirror ignores it.

3. Why does the customer need this? (List the business requirements here)
The KubeVirt provider is probably the most common/used provider for the Hosted Control Plane and we already see a strong demand of it being used in disconnected environments.
We can provide workarounds and scripts to manually handle the mirroring of this image, but the user experience will be by far less than optimal providing bad feelings on a day-0 activity.

4. List any affected packages or components.
oc-mirror (v1/v2 ?)