FIX hybrid issue with vbmc
FIX hybrid issue with vbmc

when provisioning hybrid deployment, vbmc role tries to open ports in
iptables for the overcloud nodes and fails because they are BM.

this patch should prevent "vbmc for overcloud" task to run in case of
hybrid deployment

RHOSINFRA-1526
Change-Id: I609cdce8b84c84ed9b5dc8661dbf7c0867b381e7

redhat-openstack/infrared,redhat-openstack/infrared,redhat-openstack/infrared