V4L/DVB: saa7134: add RM-K6 remote control support for Avermedia M135A

This change adds support for one more remote control type for Avermedia
M135A (model RM-K6), shipped with Positivo machines.

Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>