ipq40xx: add MikroTik LHGG-60ad outdoor 802.11ad (60GHz) dish

ipq40xx: add MikroTik LHGG-60ad outdoor 802.11ad (60GHz) dish

LHGG-60ad is IPQ4019 + wil6210 based.

Specification:

- Qualcomm IPQ4019 (717 MHz)
- 256 MB of RAM (DDR3L)
- 16 MB (SPI NOR) of flash
- 1x Gbit ethernet, 802.3af/at POE IN connected through AR8035.
- WLAN: wil6210 802.11ad PCI card
- No USB or SD card ports
- UART disabled
- 8x LEDs

Biggest news is the wil6210 PCI card.
Integration for its configuration and detection has already been taken
care of when adding support for TP-Link Talon AD7200.
However, signal quality is much lower than with stock firmware, so
probably additional board-specific data has to be provided to the
driver and is still missing at the moment.

Signed-off-by: Robert Marko <robimarko@gmail.com>
Signed-off-by: Alexander Couzens <lynxis@fe80.eu>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
[Fix Ethernet Interface]
Signed-off-by: Nick Hainke <vincent@systemli.org>