mlx5ib: Fix null pointer dereference in mlx5_ib_create_srq

Although "create_srq_user" does overwrite "in.pas" on some paths, it
also contains at least one feasible path which does not overwrite it.

Approved by:    hselasky (mentor)
MFC after:      1 week
Sponsored by:   Mellanox Technologies

sys/dev/mlx5/mlx5_ib/mlx5_ib_srq.c

@@ -287,7 +287,7 @@ struct ib_srq *mlx5_ib_create_srq(struct ib_pd *pd,
 	else
 		err = create_srq_kernel(dev, srq, &in, buf_size);
 
-	if (err) {
+	if (err || !in.pas) {
 		mlx5_ib_warn(dev, "create srq %s failed, err %d\n",
 			     pd->uobject ? "user" : "kernel", err);
 		goto err_srq;