V4L/DVB (12247): tvp514x: formatting comments as per kernel documentation

Fix documentation style based on comments from Mauro.

Reviewed by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMuralidharan Karicheri <m-karicheri2@ti.com>
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>