media: i2c: add driver for the SK Hynix Hi-846 8M pixel camera

media: i2c: add driver for the SK Hynix Hi-846 8M pixel camera

The SK Hynix Hi-846 is a 1/4" 8M Pixel CMOS Image Sensor. It supports
usual features like I2C control, CSI-2 for frame data, digital/analog
gain control or test patterns.

This driver supports the 640x480, 1280x720 and 1632x1224 resolution
modes. It supports runtime PM in order not to draw any unnecessary power.

The part is also called YACG4D0C9SHC and a datasheet can be found at
https://product.skhynix.com/products/cis/cis.go

The large sets of partly undocumented register values are for example
found when searching for the hi846_mipi_raw_Sensor.c Android driver.

Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>