Add undercloud-vm-ironic-source yaml file

Copies the undercloud-vm-source yaml file and removes portions which
were particular to nova-baremetal, replacing them and paving the way
for further Ironic-specific changes.

Change-Id: Ied49b0f8018291a0851cf2e10d83a174cb180479
Merge "Add undercloud-vm-ironic-source yaml file"