dt-bindings: vendor-prefixes: Add prefix for GalaxyCore Inc.

Add a vendor prefix entry for galaxycore (https://www.gcoreinc.com

)

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>