[media] cx231xx: Remove IR support from the driver

Polaris design uses MCE support. Instead of reinventing the wheel,
just let mceusb handle the remote controller.

Acked-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Sri Devi <Srinivasa.Deevi@conexant.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>