engine: disable fencing for gluster hosts

Power management and fencing is not supported for gluster
hosts. So VdsNotRespondingTreatment will be executed for
the hosts which belongs to a virt supported cluster.

Change-Id: I056761aba2981baa1ec4b237e93f05fc36f6380f
Bug-Url: https://bugzilla.redhat.com/956606
Signed-off-by: Kanagaraj M <kmayilsa@redhat.com>