dt-bindings: vendor-prefixes: Add Sunplus

Add vendor prefix for Sunplus Technology Co., Ltd. (http://www.sunplus.com

)

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Qin Jian <qinjian@cqplus1.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/2e74a1339a5ea54d92fdc4d1998a2b169e23b82b.1640154492.git.qinjian@cqplus1.com