arm64: dts: rockchip: Add SOQuartz Model A baseboard

This patch adds the device tree for the "Model A" baseboard for
the SOQuartz CM4 SoM, which is not to be confused with the
Quartz64 Model A, which is the same form factor and SoC, but is
not a CM4 carrier board.

The board features a PCIe 2 x1 slot, USB 2 host ports, CSI/DSI
connectors, an eDP FFC connector, gigabit ethernet, HDMI, and a
12V DC barrel jack. Also present is a microSD card slot, 40-pin
GPIO, and a power and reset button.

Signed-off-by: Andrew Powers-Holmes <aholmes@omnom.net>
[rebase, misc fixes, reword]
Signed-off-by: Nicolas Frattaroli <frattaroli.nicolas@gmail.com>
Link: https://lore.kernel.org/r/20221116115337.541601-5-frattaroli.nicolas@gmail.com


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