[media] zoran: Drop unused module parameters encoder and decoder

The ability to force the encoder or decoder chip was broken by commit
0ab6e1c3 in February 2009. As nobody
complained for over 2 years, I take it that these parameters were no
longer used so we can simply drop them.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>