IB/mlx4: Fix queue overflow check in post_recv

In mlx4_ib_post_recv(), we should check the queue for overflow using
recv_cq instead of send_cq (current code looks like a copy-and-paste
mistake).

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/mlx4/qp.c b/drivers/infiniband/hw/mlx4/qp.c
index 989555c..2a97c96 100644
--- a/drivers/infiniband/hw/mlx4/qp.c
+++ b/drivers/infiniband/hw/mlx4/qp.c
@@ -1752,7 +1752,7 @@
 	ind = qp->rq.head & (qp->rq.wqe_cnt - 1);
 
 	for (nreq = 0; wr; ++nreq, wr = wr->next) {
-		if (mlx4_wq_overflow(&qp->rq, nreq, qp->ibqp.send_cq)) {
+		if (mlx4_wq_overflow(&qp->rq, nreq, qp->ibqp.recv_cq)) {
 			err = -ENOMEM;
 			*bad_wr = wr;
 			goto out;