RDMA/hns: Delete the not-used lines

Delete the assignment of srq->ibsrq.ext.xrc.srq_num, beacause this
value is not used.
Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Lijun Ou <oulijun@huawei.com>
Link: https://lore.kernel.org/r/1566393276-42555-9-git-send-email-oulijun@huawei.comSigned-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/hns/hns_roce_srq.c

@@ -412,7 +412,6 @@ int hns_roce_create_srq(struct ib_srq *ib_srq,
 		goto err_wrid;
 
 	srq->event = hns_roce_ib_srq_event;
-	srq->ibsrq.ext.xrc.srq_num = srq->srqn;
 	resp.srqn = srq->srqn;
 
 	if (udata) {