ar71xx: add support for TL-WR802N Version 2

This patch adds support for the TP-Link TL-WR802N Version 2.

Specification:
- SoC: Qualcomm Atheros QCA9533 (560 MHz, MIPS 24Kc)
- RAM: 32 MiB
- Storage: 4 MiB of FLash on board
- Wireless: Built into QCA9533 (Honey Bee), PHY modes b/g/n
- Ethernet: 1x100M (port0)

Installation through OEM Web Interface:
- Connect to TL-WR802N by Ethernet or Wi-Fi
- Go to http://192.168.0.1 (default user is "admin" & password is "admin)
- Go to "System Tools -> Firmware Upgrade"
- Browse for firmware "*.factory-us.bin" or  "*.factory-eu.bin" for eu model
- Click upgrade

Installation through tftp:
Note: T_OUT, T_IN and GND on the board must be connected to USB TTL
      Serial Configuration 115200 8n1

- Boot the TL-WR802N
- When "Autobooting in 1 seconds" appears type "tpl" followed by enter
- Connect to the board Ethernet port
    (IPADDR: 192.168.1.1, ServerIP: 192.168.1.10)
- tftpboot 0x80000000 <Firmware Image Name>
- Record the result of "printenv bootcmd"
- Enter "erase <Result of 'printenv bootcmd'> +0x3c0000"
    (e.g erase 0x9f020000 +0x3c0000)
- Enter "cp.b 0x80000000 <Result of 'printenv bootcmd'> 0x3c0000"
    (e.g cp.b 0x80000000 0x9f020000 0x3c0000)
- Enter "bootm <Result of 'printenv bootcmd'>"
    (e.g bootm 0x9f020000)

Signed-off-by: Thomas Roberts <tom.p.roberts@gmail.com>

target/linux/ar71xx/base-files/etc/board.d/01_leds

@@ -667,6 +667,9 @@ tl-wpa8630)
 tl-wr802n-v1)
 	ucidef_set_led_wlan "wlan" "WLAN" "tp-link:blue:system" "phy0tpt"
 	;;
+tl-wr802n-v2)
+	ucidef_set_led_wlan "wlan" "WLAN" "$board:green:system" "phy0tpt"
+	;;
 tl-wr940n-v4|\
 tl-wr941nd-v6)
 	ucidef_set_led_netdev "wan" "WAN" "tp-link:blue:wan" "eth0"

target/linux/ar71xx/base-files/etc/board.d/02_network

@@ -116,6 +116,7 @@ ar71xx_setup_interfaces()
 	tl-wa901nd-v4|\
 	tl-wr703n|\
 	tl-wr802n-v1|\
+	tl-wr802n-v2|\
 	tube2h|\
 	unifiac-lite|\
 	wndap360|\

target/linux/ar71xx/base-files/etc/diag.sh

@@ -26,6 +26,7 @@ get_status_led() {
 	minibox-v1|\
 	som9331|\
 	sr3200|\
+	tl-wr802n-v2|\
 	xd3200)
 		status_led="$board:green:system"
 		;;