IB/core: Add GID change event

Add IB GID change event type.  This is needed for IBoE when the HW
driver updates the GID (e.g when new VLANs are added/deleted) table
and the change should be reflected to the IB core cache.

Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.co.il>
Signed-off-by: Roland Dreier <roland@purestorage.com>

include/rdma/ib_verbs.h

@@ -350,7 +350,8 @@ enum ib_event_type {
 	IB_EVENT_SRQ_ERR,
 	IB_EVENT_SRQ_LIMIT_REACHED,
 	IB_EVENT_QP_LAST_WQE_REACHED,
-	IB_EVENT_CLIENT_REREGISTER
+	IB_EVENT_CLIENT_REREGISTER,
+	IB_EVENT_GID_CHANGE,
 };
 
 struct ib_event {