RDMA/hns: Update the usage of ack timeout in hip08

The ack timeout's value in qp context shall be a 5-bit value
and be assgined by users. When at of qpc is set zero, the
timer is disabled.

When attr_mask set for IB_QP_TIMEOUT, The ack timeout field
is effective.
Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Wei Hu (Xavier) <xavier.huwei@huawei.com>
Signed-off-by: Shaobo Xu <xushaobo2@huawei.com>
Signed-off-by: Yixian Liu <liuyixian@huawei.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/hns/hns_roce_hw_v2.c

@@ -2725,15 +2725,12 @@ static int modify_qp_rtr_to_rts(struct ib_qp *ibqp,
 	roce_set_field(qpc_mask->byte_212_lsn, V2_QPC_BYTE_212_LSN_M,
 		       V2_QPC_BYTE_212_LSN_S, 0);
 
-	if (attr->timeout < 0xf)
-		roce_set_field(context->byte_28_at_fl, V2_QPC_BYTE_28_AT_M,
-			       V2_QPC_BYTE_28_AT_S, 0xf);
-	else
+	if (attr_mask & IB_QP_TIMEOUT) {
 		roce_set_field(context->byte_28_at_fl, V2_QPC_BYTE_28_AT_M,
 			       V2_QPC_BYTE_28_AT_S, attr->timeout);
-
-	roce_set_field(qpc_mask->byte_28_at_fl, V2_QPC_BYTE_28_AT_M,
-		       V2_QPC_BYTE_28_AT_S, 0);
+		roce_set_field(qpc_mask->byte_28_at_fl, V2_QPC_BYTE_28_AT_M,
+			      V2_QPC_BYTE_28_AT_S, 0);
+	}
 
 	roce_set_field(context->byte_28_at_fl, V2_QPC_BYTE_28_SL_M,
 		       V2_QPC_BYTE_28_SL_S,