dt-bindings: arm: rockchip: Add Pine64 QuarzPro64

Add devicetree binding documentation for Pine64 QuartzPro64 SBC.

Signed-off-by: Ondrej Jirman <megi@xff.cz>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20231011215856.2082241-2-megi@xff.cz


Signed-off-by: Heiko Stuebner <heiko@sntech.de>