1. Proposed title of this feature request
vSphere stretched cluster support

2. What is the nature and description of the request? (describe in detail)
Currently vSphere topology for MachineSet and IPI installations requires labels openshift-region to be set on datacenter and openshift-zone to be set on a compute cluster. To support a stretched cluster the openshift-zone label should be recognized on a hostgroup or on a host level to indicate which hosts belong to a zone within the same compute cluster.

3. Why it is needed? (List the business requirements here)
Some setups does not follow the compute cluster per zone directive and to cover this use case, something like the above solution is required.

4. List any affected packages or components