arm64: dts: rockchip: Add gru-scarlet-dumo board

Dumo is another variant of Scarlet, also known as the ASUS Chromebook
Tablet CT100. This is almost the same as Scarlet-Innolux, but uses a
board-specific calibration variant for the WiFi module.

Add a new device tree for it.

Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20210812094753.2359087-3-wenst@chromium.org


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