media: i2c: Add driver for Sony IMX219 sensor

Commit 1283b3b8

 upstream.
(Currently on linux-media/master, queued for 5.7)

Adds a driver for the 8MPix Sony IMX219 CSI2 sensor.
Whilst the sensor supports 2 or 4 CSI2 data lanes, this driver
currently only supports 2 lanes.
8MPix @ 15fps, 1080P @ 30fps (cropped FOV), and 1640x1232 (2x2 binned)
@ 30fps are currently supported.

[Sakari Ailus: make imx219_check_hwcfg static]

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Andrey Konovalov <andrey.konovalov@linaro.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>