IB/qib: Remove qib multicast verbs functions

Multicast is now supported by rdmavt. Remove the verbs multicast functions
and use that.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Harish Chegondi <harish.chegondi@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/qib/qib_qp.c

@@ -310,8 +310,6 @@ unsigned qib_free_all_qps(struct rvt_dev_info *rdi)
 	for (n = 0; n < dd->num_pports; n++) {
 		struct qib_ibport *ibp = &dd->pport[n].ibport_data;
 
-		if (!qib_mcast_tree_empty(ibp))
-			qp_inuse++;
 		rcu_read_lock();
 		if (rcu_dereference(ibp->rvp.qp[0]))
 			qp_inuse++;