dt-bindings: arm: rockchip: Add Orange Pi 5 board

Add Orange Pi 5 SBC from Xunlong.

Signed-off-by: Muhammed Efe Cetin <efectn@6tel.net>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/89e92c8df546a0b926ba7481aa83c1945e81e8a4.1696878787.git.efectn@6tel.net
Signed-off-by: Heiko Stuebner <heiko@sntech.de>