media: soc_camera: ov9640: move ov9640 out of soc_camera

Initial part of ov9640 transition from soc_camera subsystem to a standalone
v4l2 subdevice. The soc_camera version seems to be used only in Palm Zire72
and in (the future) HTC Magician. On these two devices the support is
broken as pxa_camera driver doesn't use soc_camera anymore. The other
mentions from git grep are "TODOs" (in board-osk.c) or chip names for
unsupported sensors on HW which doesn't use soc_camera at all (irelevant).

Copy the driver files from soc_camera and mark the original ones in the
Kconfig description as obsoleted.

Add config option VIDEO_OV9640 to the build files in drivers/media/i2c.

Signed-off-by: Petr Cvek <petrcvekcz@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>