[media] media: rc: nuvoton: clean up initialization of wakeup registers

The registers defining wakeup sequence handling are set when the
wakeup sequence is set via sysfs. There's no need to initialize them
otherwise.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>