[media] lgdt3305: we only need to pass state into lgdt3305_mpeg_mode_polarity()

Simplify the code a little bit by removing some uneeded arguments
to lgdt3305_mpeg_mode_polarity().

Signed-off-by: Michael Ira Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>