Hypervisor support for MNO clusters

[josecastillolema]

It would be nice to have the ability to host workers from MNO clusters in hypervisors.

[radez]

Proof of concept working with 1 virtual worker.

• Generate Inventory with no workers and HV turned on
• update workers count and allocation_node_count
• copy {workers count} entries from [hv_vm] to [workers]
• update mac_address to network_mac
• code changes to handle missing lab_mac (vms won't have a lab_mac)
• added libvirt vendor definition to boot-iso role

Working on generating a patch to handle this and how to work around having to copy workers from hv_vm to worker inventory sections.
Working on being able to do more workers (this is related to handling lab mac properly)