qualcommax: ipq60xx: add support for Netgear WAX610 and WAX610Y

qualcommax: ipq60xx: add support for Netgear WAX610 and WAX610Y

Netgear WAX610 / WAX610Y is a 802.11ax AP claiming AX1800 support.

Specifications:
---------------
* CPU: Qualcomm IPQ6018 Quad core Cortex-A53
* RAM: 512MB
* Storage: Winbond W29N01HZBINF 128MB NAND
* Ethernet:
  * 2.5GbE RJ45 port with PoE input
* WLAN:
  * 2.4GHz/5GHz
* LEDs:
  * Power: Dual-color LED (Green / Orange), Single-color LED (Blue)
  * Ethernet: Dual-color LED (Green / Orange)
  * 2.4Ghz WiFi: 2x Single-color LED (Blue, Green)
  * 5Ghz WiFi: 2x Single-color LED (Blue, Green)
* Buttons:
  * 1x Reset
* UART: 4-pin populated header
  * Pinout 1 - VCC, 2 - GND, 3 - TX, 4 - RX

Installation:
=============

Web UI method
-------------

Set up the device using the stock web UI in local management mode.

Download the ui-factory.tar image.
 * Enter the Management tab
 * Select Maintenance->Upgrade->Firmware Upgrade
 * Ensure the "Upgrade Options" field has "Local" selected
 * Click "Browse File" and select the image
 * Click "Upgrade" (NOT "Upgrade Now") at the bottom of the page

The device will install the image but reboot back into the vendor
firmware. Return the to Firmware Upgrade page as above and select
"Boot up Backup Firmware". The device should reboot into OpenWRT.

TFTP method
-----------

To flash via tftp, first place the initramfs image on the TFTP server.

    setenv serverip <ip of tftp server>
    setenv ipaddr <ip in same subnet as tftp server>
    tftpboot netgear_wax610-initramfs-uImage.itb
    bootm

This should boot OpenWRT. Once booted, flash the sysupgrade.bin image
using either luci or the command line.

Signed-off-by: Erik Servili <serverror@serverror.com>
Link: https://github.com/openwrt/openwrt/pull/18377
Signed-off-by: Robert Marko <robimarko@gmail.com>