board: rockchip: Add Hardkernel ODROID-M1

Hardkernel ODROID-M1 is a single board computer with a RK3568B2 SoC,
a slightly modified version of the RK3568 SoC.

Features tested on a ODROID-M1 8GB v1.0 2022-06-13:
- SD-card boot
- eMMC boot
- SPI Flash boot
- PCIe/NVMe/AHCI
- SATA port
- USB host

Device tree is imported from linux v6.4.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Tested-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>