net/mlx5: Fix an IS_ERR() vs NULL bug in esw_qos_move_node()

The __esw_qos_alloc_node() function returns NULL on error.  It doesn't
return error pointers.  Update the error checking to match.

Fixes: 96619c4 ("net/mlx5: Add support for setting tc-bw on nodes")
Signed-off-by: Dan Carpenter <[email protected]>
Reviewed-by: Tariq Toukan <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: Dan Carpenter

drivers/net/ethernet/mellanox/mlx5/core/esw/qos.c

@@ -1405,9 +1405,10 @@ esw_qos_move_node(struct mlx5_esw_sched_node *curr_node)
 
 	new_node = __esw_qos_alloc_node(curr_node->esw, curr_node->ix,
 					curr_node->type, NULL);
-	if (!IS_ERR(new_node))
-		esw_qos_nodes_set_parent(&curr_node->children, new_node);
+	if (!new_node)
+		return ERR_PTR(-ENOMEM);
 
+	esw_qos_nodes_set_parent(&curr_node->children, new_node);
 	return new_node;
 }