media: i2c: mt9t112: Remove soc_camera dependencies

Remove soc_camera framework dependencies from mt9t112 sensor driver.
- Handle clk, gpios and power routines
- Register async subdev
- Remove deprecated g/s_mbus_config operations
- Remove driver flags
- Change driver interface and add kernel doc
- Adjust build system
- Fix code style issues reported by checkpatch in strict mode

This commit does not remove the original soc_camera based driver as long
as other platforms depends on soc_camera framework.

As I don't have access to a working camera module, this change has only
been compile tested.

Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>