V4L/DVB (6408): Cleanup: Removed obsoleted code from bttv-cards

This is part of the old V4L1->V4L2 bttv patch, ported to current tree
by Mauro Carvalho Chehab <mchehab@infradead.org>

Signed-off-by: Nickolay V. Shmyrev <nshmyrev@yandex.ru>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>