media: i2c: gc0308: new driver

Introduce new driver for GalaxyCore GC0308, which is a cheap
640x480 with an on-chip ISP sensor sold since 2010. Data is
provided via parallel bus.

Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
[Sakari Ailus: Changed MAINTAINERS to match GC2145 entry.]
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>