core, engine, db: Enable suspend, migration and memory snapshots in ppc64

This patch enables features that are working in PowerKVM: VM suspend,
migration and memory snapshots.

Change-Id: Ic4e1bddae604f4266af40f45fab40592907b007a
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1156186
Signed-off-by: Vitor de Lima <vdelima@redhat.com>