net/mlx5: HWS, check the correct variable in hws_send_ring_alloc_sq()

There is a copy and paste bug so this code checks "sq->dep_wqe" where
"sq->wr_priv" was intended.  It could result in a NULL pointer
dereference.

Fixes: 2ca6259 ("net/mlx5: HWS, added send engine and context handling")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/da822315-02b7-4f5b-9c86-0d5176c5069d@stanley.mountain
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: Dan Carpenter

drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_send.c

@@ -584,7 +584,7 @@ static int hws_send_ring_alloc_sq(struct mlx5_core_dev *mdev,
 	}
 
 	sq->wr_priv = kzalloc(sizeof(*sq->wr_priv) * buf_sz, GFP_KERNEL);
-	if (!sq->dep_wqe) {
+	if (!sq->wr_priv) {
 		err = -ENOMEM;
 		goto free_dep_wqe;
 	}