media: zoran: Add vb_queue

This patchs adds a vb_queue without using it.
This reduce the final VB2 conversion patch.

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