arm64: dts: rockchip: Add SOQuartz blade board

arm64: dts: rockchip: Add SOQuartz blade board

This adds a device tree for the PINE64 SOQuartz blade baseboard,
a 1U rack mountable baseboard for the CM4 form factor with PoE
support designed for the SOQuartz CM4 System-on-Module.

The board takes power from either PoE or a 5V DC input, and allows
for mounting an M.2 SSD.

The board also features one USB 2.0 host port, one HDMI output,
a 3.5mm jack for UART, and the aforementioned gigabit networking
port.

Signed-off-by: Andrew Powers-Holmes <aholmes@omnom.net>
[rebase, squash, reword, misc fixes]
Signed-off-by: Nicolas Frattaroli <frattaroli.nicolas@gmail.com>
Link: https://lore.kernel.org/r/20221116115337.541601-3-frattaroli.nicolas@gmail.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>