media: staging: media: zoran: rename debug module parameter

All zoran module will be merged, so to prevent conflict, the debug
module parameter need to be renamed

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>