media: rc: per-protocol repeat period

CEC needs a keypress timeout of 550ms, which is too high for the IR
protocols. Also fill in known repeat times, with 50ms error margin.

Also, combine all protocol data into one structure.

Signed-off-by: Sean Young <sean@mess.org>
Suggested-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>