RDMA/ocrdma: Query and initalize the PFC SL

This patch implements routine to query the PFC priority from the
adapter port.

Following are the changes implemented:

 * A new FW command is implemented to query the operational/admin DCBX
   configuration from the FW and obtain active priority(service
   level).
 * Adds support for the async event reported by FW when the PFC
   priority changes. Service level is re-initialized during modify_qp
   or create_ah, based on this event.
 * Maintain SL value in ocrdma_dev structure and refer that as and
   when needed.

Signed-off-by: Devesh Sharma <devesh.sharma@emulex.com>
Signed-off-by: Selvin Xavier <selvin.xavier@emulex.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/hw/ocrdma/ocrdma_ah.c

@@ -100,6 +100,8 @@ struct ib_ah *ocrdma_create_ah(struct ib_pd *ibpd, struct ib_ah_attr *attr)
 	if (!(attr->ah_flags & IB_AH_GRH))
 		return ERR_PTR(-EINVAL);
 
+	if (atomic_cmpxchg(&dev->update_sl, 1, 0))
+		ocrdma_init_service_level(dev);
 	ah = kzalloc(sizeof(*ah), GFP_ATOMIC);
 	if (!ah)
 		return ERR_PTR(-ENOMEM);