IB/mlx5: Honor cnt_set_id_valid flag instead of set_id

It is incorrect to depend on set_id value to know if counters were
allocated or not. set_id_valid field is set to true when counters
were allocated. Therefore, use set_id_valid while deciding to
free counters.

Cc: <stable@vger.kernel.org> # 4.15
Fixes: aac4492ef23a ("IB/mlx5: Update counter implementation for dual port RoCE")
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/mlx5/main.c

@@ -4699,7 +4699,7 @@ static void mlx5_ib_dealloc_counters(struct mlx5_ib_dev *dev)
 	int i;
 
 	for (i = 0; i < dev->num_ports; i++) {
-		if (dev->port[i].cnts.set_id)
+		if (dev->port[i].cnts.set_id_valid)
 			mlx5_core_dealloc_q_counter(dev->mdev,
 						    dev->port[i].cnts.set_id);
 		kfree(dev->port[i].cnts.names);