media: gspca: ov534-ov772x: add SGBRG8 bayer mode support

Add support to pass through the sensor's native SGBRG8 bayer pattern,
allowing to cut the required USB bandwidth in half.

Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>