arm64: dts: rockchip: add overlay for PX30 Ringneck Haikou Video Demo adapter

arm64: dts: rockchip: add overlay for PX30 Ringneck Haikou Video Demo adapter

This adds support for the video-demo-adapter DEVKIT ADDON CAM-TS-A01
(https://embedded.cherry.de/product/development-kit/) for the Haikou
devkit with PX30 Ringneck SoM.

The Video Demo adapter is an adapter connected to the fake PCIe slot
labeled "Video Connector" on the Haikou devkit.

Itss main feature is a Leadtek DSI-display with touchscreen and a camera
(that is not supported yet because the expected clock rate by the driver
cannot be exactly reached by the clock driver). To drive these
components a number of additional regulators are grouped on the adapter
as well as a PCA9670 gpio-expander to provide the needed additional
gpio-lines.

Signed-off-by: Quentin Schulz <quentin.schulz@cherry.de>
Link: https://lore.kernel.org/r/20250221-ringneck-dtbos-v2-4-310c0b9a3909@cherry.de
Signed-off-by: Heiko Stuebner <heiko@sntech.de>