[media] ati_remote: add regular up/down buttons to Medion Digitainer keymap

[media] ati_remote: add regular up/down buttons to Medion Digitainer keymap

There are many different Medion X10 remotes that need slightly different
keymaps. We may not yet have all the needed keymaps, in which case a
wrong keymap may be used. This happened with Medion X10 OR2x remotes
before the keymap for them was added, causing the ati_remote driver to
select the Medion Digitainer keymap instead. Unfortunately, the Medion
Digitainer keymap doesn't have the standard X10 up/down scancodes
assigned to KEY_UP and KEY_DOWN keycodes, making wrongly assigned
remotes mostly unusable.

Add the regular KEY_UP and KEY_DOWN scancodes to the Medion X10
Digitainer keymap, making any Medion remote mostly usable even when
wrongly used with that keymap (standard buttons, such as
up/down/left/right, 0-9, play/stop/pause, have the same scancode in all
the X10 remotes).

Signed-off-by: Anssi Hannula <anssi.hannula@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>