ath79: add support for TP-Link TL-WDR4900 v2

Specification:
- SoC: Qualcomm Atheros QCA9558
- Flash: 8 MB
- RAM: 128 MB
- Ethernet: AR8327N with 5 GE ports.
- Wireless radio: QCA9558 for 2.4G and AR9580 for 5G.

Flash instruction:
  Upload the generated factory firmware on web interface.

Signed-off-by: Chuanhong Guo <gch981213@gmail.com>

target/linux/ath79/base-files/etc/board.d/02_network

@@ -69,7 +69,8 @@ ath79_setup_interfaces()
 		ucidef_add_switch "switch0" \
 			"0@eth0" "3:lan:1" "5:lan:2" "4:wan"
 		;;
-	tplink,archer-c7-v2)
+	tplink,archer-c7-v2|\
+	tplink,tl-wdr4900-v2)
 		ucidef_add_switch "switch0" \
 			"0@eth1" "2:lan" "3:lan" "4:lan" "5:lan" "6@eth0" "1:wan"
 		;;

target/linux/ath79/base-files/etc/hotplug.d/firmware/10-ath9k-eeprom

@@ -52,7 +52,8 @@ case "$FIRMWARE" in
 		;;
 	ocedo,raccoon|\
 	tplink,tl-wdr3600|\
-	tplink,tl-wdr4300)
+	tplink,tl-wdr4300|\
+	tplink,tl-wdr4900-v2)
 		ath9k_eeprom_extract "art" 20480 1088
 		;;
 	netgear,wnr612-v2|\