Remove soc_camera framework dependencies from ov772x sensor driver.
- Handle clock and gpios
- Register async subdevice
- Remove soc_camera specific g/s_mbus_config operations
- Change image format colorspace from JPEG to SRGB as the two use the
  same colorspace information but JPEG makes assumptions on color
  components quantization that do not apply to the sensor
- Remove sizes crop from get_selection as driver can't scale
- Add kernel doc to driver interface header file
- Adjust build system

This commit does not remove the original soc_camera based driver as long
as other platforms depends on soc_camera-based CEU driver.
Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>