engine: Expand nics filter criteria

The engine query for retrieving the host nics should
consider nics which aren't bonds either by
VdsNetworkInterface.getBonded() being equal to null or
to Boolean.False.

Change-Id: I587e51efaf935fafbfbe814bb4a1f1dea1a5ab94
Bug-Url: https://bugzilla.redhat.com/1011486
Signed-off-by: Moti Asayag <masayag@redhat.com>