get_maintainer: add Alan to .get_maintainer.ignore

Alan asked to be added to the .get_maintainer.ignore list.

Link: https://lkml.kernel.org/r/YvN30KhO9aD5Sza9@kili
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>