dt-bindings: gpio: rockchip: add gpio-ranges

Allow usage of gpio-ranges with the rockchip gpio controller. The driver
already had support for this since it has been added to the mainline kernel
in the first place.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

Documentation/devicetree/bindings/gpio/rockchip,gpio-bank.yaml

@@ -27,6 +27,8 @@ properties:
       - description: APB interface clock source
       - description: GPIO debounce reference clock source
 
+  gpio-ranges: true
+
   gpio-controller: true
 
   gpio-line-names: true