ramips: mt76x8: add support for Cudy RE1200 Outdoor v1

ramips: mt76x8: add support for Cudy RE1200 Outdoor v1

Hardware:
 - SoC: MediaTek MT7628DAN
 - Flash: 8 MiB XMC 25QH64CHIQ
 - RAM: 64 MiB (integrated on SoC)
 - WLAN: 2.4 GHz (MT7603E, 11n), 5 GHz (MediaTek MT7613BEN, 11ac)
 - Ethernet: 1x10/100 Mbps LAN
 - Buttons: 1 Reset button, 1 WPS button
 - LEDs: 5x Green
 - Serial Console: unpopulated header 115200 8n1
 - Power: 24v Passive POE

MAC addresses:
+---------+-------------------+-----------+
|         | MAC               | Algorithm |
+---------+-------------------+-----------+
| LAN     | 80:af:ca:xx:xx:x0 | label     |
| WLAN 2g | 80:af:ca:xx:xx:x0 | label     |
| WLAN 5g | 80:af:ca:xx:xx:x2 | +2        |
+---------+-------------------+-----------+

Installation:
Please check the Wiki for this device for a more convenient solution than the one below.

1. Disassemble the device, desolder and dump the flash chip with a SPI programmer.
2. Separate the partitions with dd:

dd if=spi_dump.bin of=u-boot.bin     bs=1  skip=0        count=196608  status=progress
dd if=spi_dump.bin of=u-boot-env.bin bs=1  skip=196608   count=65536   status=progress
dd if=spi_dump.bin of=factory.bin    bs=1  skip=262144   count=65536   status=progress
dd if=spi_dump.bin of=firmware.bin   bs=1  skip=327680   count=7995392 status=progress
dd if=spi_dump.bin of=bdinfo.bin     bs=1  skip=8323072   count=65536   status=progress

3. Download the sysupgrade firmware at openwrt.bin.
4. The firmware size should be 7995392 bytes. Fix the size of your firmware putting zeros to the end, with:

truncate -s 7995392 firmware.bin

5. Combine all the parititions:

cat u-boot.bin u-boot-env.bin factory.bin openwrt.bin bdinfo.bin > spi_new.bin

6. Erase and flash the SPI chip with the new file. Solder the chip and boot the router.

Signed-off-by: Luis Mita <luis@luismita.com>
Link: https://github.com/openwrt/openwrt/pull/20381
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>