Revert "net/mlx5: Annotate mutex destroy for root ns"

This reverts commit 9b035b0 which is
commit 9ca4153 upstream.

It was backported incorrectly, Paul writes at:
	https://lore.kernel.org/r/20200607203425.GD23662@windriver.com

	I happened to notice this commit:

	9ca4153 - "net/mlx5: Annotate mutex destroy for root ns"

	...was backported to 4.19 and 5.4 and v5.6 in linux-stable.

	It patches del_sw_root_ns() - which only exists after v5.7-rc7 from:

	6eb7a26 - "net/mlx5: Don't maintain a case of del_sw_func being
	null"

	which creates the one line del_sw_root_ns stub function around
	kfree(node) by breaking it out of tree_put_node().

	In the absense of del_sw_root_ns - the backport finds an identical one
	line kfree stub fcn - named del_sw_prio from this earlier commit:

	139ed6c - "net/mlx5: Fix steering memory leak"  [in v4.15-rc5]

	and then puts the mutex_destroy() into that (wrong) function, instead of
	putting it into tree_put_node where the root ns case used to be hand

Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Roi Dayan <roid@mellanox.com>
Cc: Mark Bloch <markb@mellanox.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

@@ -416,12 +416,6 @@ static void del_sw_ns(struct fs_node *node)
 
 static void del_sw_prio(struct fs_node *node)
 {
-	struct mlx5_flow_root_namespace *root_ns;
-	struct mlx5_flow_namespace *ns;
-
-	fs_get_obj(ns, node);
-	root_ns = container_of(ns, struct mlx5_flow_root_namespace, ns);
-	mutex_destroy(&root_ns->chain_lock);
 	kfree(node);
 }