IB/mlx5: Fix return value check in flow_counters_set_data()

In case of error, the function mlx5_fc_create() returns ERR_PTR() and
never returns NULL. The NULL test in the return value check should be
replaced with IS_ERR().

Fixes: 3b3233fb ("IB/mlx5: Add flow counters binding support")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/mlx5/main.c

@@ -3199,8 +3199,8 @@ static int flow_counters_set_data(struct ib_counters *ibcounters,
 	if (!mcounters->hw_cntrs_hndl) {
 		mcounters->hw_cntrs_hndl = mlx5_fc_create(
 			to_mdev(ibcounters->device)->mdev, false);
-		if (!mcounters->hw_cntrs_hndl) {
-			ret = -ENOMEM;
+		if (IS_ERR(mcounters->hw_cntrs_hndl)) {
+			ret = PTR_ERR(mcounters->hw_cntrs_hndl);
 			goto free;
 		}
 		hw_hndl = true;