V4L/DVB (9386): FIX: Add in missing inversion (should be ideally in the config struct)

Thanks to Marco Schluessler <marco@lordzodiac.de> for pointing it out

Signed-off-by: Manu Abraham <manu@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>