ramips: add support for Netgear R6120

This patch adds support for the Netgear R6120, aka Netgear AC1200.

Specification:
- SoC: MediaTek MT7628 (580 MHz)
- Flash: 16 MiB
- RAM: 64 MiB
- Wireless: 2.4Ghz(builtin) and 5Ghz (MT7612E)
- LAN speed: 10/100
- LAN ports: 4
- WAN speed: 10/100
- WAN ports: 1
- Serial baud rate of Bootloader and factory firmware: 57600

To flash use nmrpflash with the provided factory.img.
Flashing via webinterface will not work, for now.

Signed-off-by: Ludwig Thomeczek <ledesrc@wxorx.net>

target/linux/ramips/base-files/etc/board.d/01_leds

@@ -319,6 +319,11 @@ mzk-ex750np)
 na930)
 	set_usb_led "$boardname:blue:status"
 	;;
+netgear,r6120)
+	ucidef_set_led_switch "lan" "lan" "$boardname:green:lan" "switch0" "0x0f"
+	ucidef_set_led_wlan "wlan2g" "WiFi 2.4GHz" "$boardname:green:wlan2g" "phy0tpt"
+	ucidef_set_led_wlan "wlan5g" "WiFi 5GHz" "$boardname:green:wlan5g" "phy1tpt"
+	;;
 newifi-d1)
 	set_usb_led "$boardname:red:status"
 	;;

target/linux/ramips/base-files/etc/board.d/02_network

@@ -103,6 +103,7 @@ ramips_setup_interfaces()
 	mzk-750dhp|\
 	mzk-w300nh2|\
 	d-team,newifi-d2|\
+	netgear,r6120|\
 	nixcore-x1-8M|\
 	nixcore-x1-16M|\
 	oy-0001|\