Configurable host network for inventory
Configurable host network for inventory

This patch makes the host network configurable in the ansible inventory.
Previously, this was always hardcoded to ctlplane. In some cases, there
may be no ctlplane network (possible with deployed-server), and another
network will need to be used to connect to the overcloud nodes.

Change-Id: I132a2f2bec3d26ceeec0d8dc0eee85675b75dd04

openstack/tripleo-common,openstack/tripleo-common