Fix the W=1 build warning:
../fs/namespace.c:3050: warning: Function parameter or member 'mp' not described in 'can_move_mount_beneath'
Signed-off-by: Christian Brauner <brauner@kernel.org>
* can_move_mount_beneath - check that we can mount beneath the top mount
* @from: mount to mount beneath
* @to: mount under which to mount
+ * @mp: mountpoint of @to
*
* - Make sure that @to->dentry is actually the root of a mount under
* which we can mount another mount.