media: atomisp: Drop atomisp-ov2680 sensor driver

After recent improvements to atomisp and the standard ov2680
sensor driver, the atomisp driver now works fine with
the standard ov2680 driver.

Drop the no longer necessary atomisp specific atomisp-ov2680
sensor driver.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>