Remove the remaining two obsolete usb-serial subdriver entries from
MAINTAINERS, which were missed in the recent purge by commit
f896b796 ("USB: Maintainers change for usb serial drivers").
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NOliver Neukum <oliver@neukum.org>
Signed-off-by: NMatthias Urlichs <matthias@urlichs.de>