media: i2c: Add driver for onsemi MT9M114 camera sensor

The MT9M114 is a CMOS camera sensor that combines a 1296x976 pixel array
with a 10-bit dynamic range together with an internal ISP. The driver
exposes two subdevs, one for the pixel array and one for the ISP (named
IFP for Image Flow Processor). Major supported features are

- Full configuration of analog crop and binning in the pixel array
- Full configuration of scaling in the ISP
- Automatic exposure and white balance
- Manual exposure and analog gain
- Horizontal and vertical flip

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>