libhns: Fix no locking in the exception branch of wr start()

[ Upstream commit d1d0ac5 ]

According to the man page ibv_wr_post.3.md,
"The provider should provide locking to ensure that ibv_wr_start()
and ibv_wr_complete()/abort() form a per-QP critical section
where no other threads can enter."

Currently the exception branch of wr_start() is not locked, add
a lock here.

Fixes: 36446a5 ("libhns: Extended QP supports the new post send mechanism")
Signed-off-by: wenglianfa <wenglianfa@huawei.com>
Signed-off-by: Junxian Huang <huangjunxian6@hisilicon.com>
Signed-off-by: Nicolas Morey <nmorey@suse.com>

providers/hns/hns_roce_u_hw_v2.c

@@ -2530,6 +2530,7 @@ static void wr_start(struct ibv_qp_ex *ibv_qp)
 	if (state == IBV_QPS_RESET ||
 	    state == IBV_QPS_INIT ||
 	    state == IBV_QPS_RTR) {
+		pthread_spin_lock(&qp->sq.lock);
 		qp->err = EINVAL;
 		return;
 	}