media: dt-bindings: i2c: add GalaxyCore GC08A3 image sensor

Add YAML device tree binding for GC08A3 CMOS image sensor,
and the relevant MAINTAINERS entries.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Zhi Mao <zhi.mao@mediatek.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>