Use defaults for overcloud_nodes group
Use defaults for overcloud_nodes group

Deployments without overcloud nodes fail.

Change-Id: Ife98385f57bbc1a03c20f021cdb10c0eb973a9c6

okolisny/InfraRed,okolisny/InfraRed,redhat-openstack/infrared,okolisny/InfraRed,redhat-openstack/infrared,redhat-openstack/infrared