V4L/DVB (13195): gspca - gl860: comment changes and naming scheme egalization

- small changes in comments
- unified naming scheme for subdriver variables

Signed-off-by: Olivier Lorin <o.lorin@laposte.net>
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>