apparmor: update ctime whenever the mtime changes on an inode

In general, when updating the mtime on an inode, one must also update
the ctime. Add the missing ctime updates.

Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-5-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>