[media] cx231xx-417: share ioctls with cx231xx-video

Share tuner, frequency, debug and input ioctls with cx231xx-video.
These are all shared resources, so no need to implement them again.

[mchehab@redhat.com: Fix merge conflict and a checkpatch issue]
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>