V4L/DVB (3278): convert diagnostics over to the new v4l2-common.h macros.

- Convert diagnostics over to the new v4l2-common.h macros.
- deprecated tuner_debug option, the new option is debug.
- renamed cx25840_debug to debug.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>