rockchip: add support for Radxa ROCK 5B+

rockchip: add support for Radxa ROCK 5B+

The Radxa ROCK 5B+ is a single board computer using the Rockchip
RK3588 SoC.

- https://radxa.com/products/rock5/5bp

Hardware
--------

- Quad Cortex-A76 and Quad Cortex-A55 CPU
- Mali-G610 MP4 GPU
- 6 TOPS NPU
- 4/8/16/24/32GB LPDDR5 RAM
- 16/32/64/128/256GB on-board eMMC (optional)
- 16MB SPI NOR flash
- microSD card slot
- Wi-Fi 6 (Realtek RTW8852BE)
- 2.5 Gigabit Ethernet port with PoE (additional PoE HAT required)
- USB 3.1 Gen1 Type-C HOST/OTG port
- 2x USB 3.1 Gen1 Type-A HOST ports
- 2x USB 2.0 Type-A HOST ports
- 2x M.2 M Key connectors with PCIe 3.0 x2
- M.2 B Key connector
- SIM card slot
- RTC battery connector
- PWM fan connector
- 20x2 pin header
- USB Type-C power port

Installation
------------

Uncompress the OpenWrt sysupgrade and write it to a micro SD card or
eMMC using dd.

Signed-off-by: FUKAUMI Naoki <[email protected]>
Link: https://github.com/openwrt/openwrt/pull/19867
Signed-off-by: Hauke Mehrtens <[email protected]>