[media] staging: omap4iss: Compiling V4L2 framework and I2C as modules is fine

Don't require V4L2 framework and I2C being linked to the kernel directly.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>