ramips: add support for ZBT-WE1326

Specification:
- SoC: MT7621AT, MT7603EN and MT7612EN
- Flash: 16 MiB (W25Q128FVSG)
- RAM: 512 MiB (EM6GE16EWXD-12H)
- Ethernet: 1 x WAN (10/100/1000Mbps) and 4 x LAN (10/100/1000 Mbps)
- Others: USB 2.0, micro SD slot, reset button and 8 x LEDs

Issues:
- Two LEDs for 2.4 GHz and 5 GHz Wi-Fi do not work, can't find GPIOs.
- The pwr LED is not GPIO controllable

How to install:
- The original firmware is OpenWrt, so both LuCI or sysupgrade can be used.
- Do not keep settings, for sysupgrade please use the -n option.

Signed-off-by: Jiawei Wang <buaawjw@gmail.com>

target/linux/ramips/base-files/lib/ramips.sh

@@ -649,6 +649,9 @@ ramips_board_detect() {
 	*"ZBT-WA05")
 		name="zbt-wa05"
 		;;
+	*"ZBT-WE1326")
+		name="zbt-we1326"
+		;;
 	*"ZBT-WE2026")
 		name="zbt-we2026"
 		;;