devicetree: Add vendor prefix for Rikomagic

Add Rikomagic to vendor-prefixes.txt

Signed-off-by: Paweł Jarosz <paweljarosz3691@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -229,6 +229,7 @@ realtek Realtek Semiconductor Corp.
 renesas	Renesas Electronics Corporation
 richtek	Richtek Technology Corporation
 ricoh	Ricoh Co. Ltd.
+rikomagic	Rikomagic Tech Corp. Ltd
 rockchip	Fuzhou Rockchip Electronics Co., Ltd
 samsung	Samsung Semiconductor
 sandisk	Sandisk Corporation