net/mlx5: Avoid unnecessary operation

fs_get_obj retrieves the container of fs_parent_node just to pass the
same value as &fs_ns->node. Just pass fs_parent_node to
init_root_tree_recursive() to get exactly the same effect.
Signed-off-by: Eli Cohen <elic@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/fs_core.c

@@ -2395,14 +2395,12 @@ static int init_root_tree(struct mlx5_flow_steering *steering,
 			  struct init_tree_node *init_node,
 			  struct fs_node *fs_parent_node)
 {
-	int i;
-	struct mlx5_flow_namespace *fs_ns;
 	int err;
+	int i;
 
-	fs_get_obj(fs_ns, fs_parent_node);
 	for (i = 0; i < init_node->ar_size; i++) {
 		err = init_root_tree_recursive(steering, &init_node->children[i],
-					       &fs_ns->node,
+					       fs_parent_node,
 					       init_node, i);
 		if (err)
 			return err;