ipq807x-generic: Adding support for Xiaomi AX3600 based on official OpenWRT Target closes #3032

[ChristianMiddendorf]

• [x] Must be flashable from vendor firmware
  • [ ] Web interface
  • [ ] TFTP
  • [x] Other: <Sysupgrade from OpenWRT but do not save configuration over reflash... "sysupgrade -n filenamefromsysupgrade.bin">
• [x] Must support upgrade mechanism
  • [x] Must have working sysupgrade
  • [x] Must keep/forget configuration (sysupgrade [-n], firstboot)
  • [no - OpenWRT uses xiaomi_ax3600] Gluon profile name matches autoupdater image name (lua -e 'print(require("platform_info").get_image_name())') xiaomi-ax3600
• [x] Reset/WPS/... button must return device into config mode
• [x] Primary MAC address should match address on device label (or packaging) (https://gluon.readthedocs.io/en/latest/dev/hardware.html#hardware-support-in-packages)
  • When re-adding a device that was supported by an earlier version of Gluon, a factory reset must be performed before checking the primary MAC address, as the setting from the old version is not reset otherwise.
• Wired network
  • [x] should support all network ports on the device
  • [x] must have correct port assignment (WAN/LAN)
  • if there are multiple ports but no WAN port:
    • the PoE input should be WAN, all other ports LAN
    • otherwise the first port should be declared as WAN, all other ports LAN
• Wireless network (if applicable)
  • [x] Association with AP must be possible on all radios
  • [x] Association with 802.11s mesh must work on all radios
  • [x] AP+mesh mode must work in parallel on all radios
• LED mapping
  • Power/system LED
  • [x] Lit while the device is on
  • [x] Should display config mode blink sequence (https://gluon.readthedocs.io/en/latest/features/configmode.html)
  • Radio LEDs
  • [no LEDs for the radios, just one for working, one for activity] Should map to their respective radio
  • [x] Should show activity
  • Switch port LEDs
  • [x] Should map to their respective port (or switch, if only one led present)
  • [x] Should show link state and activity
• Outdoor devices only:
  • [ ] Added board name to is_outdoor_device function in package/gluon-core/luasrc/usr/lib/lua/gluon/platform.lua
• Cellular devices only:
  • [ ] Added board name to is_cellular_device function in package/gluon-core/luasrc/usr/lib/lua/gluon/platform.lua
  • [ ] Added board name with modem setup function setup_ncm_qmi to package/gluon-core/luasrc/lib/gluon/upgrade/250-cellular
• Docs:
  • [x] Added Device to docs/user/supported_devices.rst