ath79: add support for TP-Link RE450 v2

TP-Link RE450 v2 is a dual band router/range-extender
based on Qualcomm/Atheros QCA9563 + QCA9880.

Specification:

- 775 MHz CPU
- 64 MB of RAM (DDR2)
- 8 MB of FLASH (SPI NOR)
- 3T3R 2.4 GHz
- 3T3R 5 GHz
- 1x 10/100/1000 Mbps Ethernet (AR8033 PHY)
- 7x LED, 4x button
- UART header on PCB (needs unmounted R64 & R69 0201 resistors/jumpers)

Flash instruction:
Apply factory image in OEM firmware web-gui.

U-Boot does not seem to have any recovery functions, so
debricking requires connection via UART.

Signed-off-by: Peter Lundkvist <peter.lundkvist@gmail.com>

target/linux/ath79/image/common-tp-link.mk

@@ -1,4 +1,4 @@
-DEVICE_VARS += TPLINK_HWID TPLINK_HWREV TPLINK_FLASHLAYOUT TPLINK_HEADER_VERSION TPLINK_BOARD_NAME
+DEVICE_VARS += TPLINK_HWID TPLINK_HWREV TPLINK_FLASHLAYOUT TPLINK_HEADER_VERSION TPLINK_BOARD_NAME TPLINK_BOARD_ID
 
 define rootfs_align
 $(patsubst %-256k,0x40000,$(patsubst %-128k,0x20000,$(patsubst %-64k,0x10000,$(patsubst squashfs%,0x4,$(patsubst root.%,%,$(1))))))

target/linux/ath79/image/generic-tp-link.mk

@@ -13,6 +13,24 @@ define Device/tl-archer-c7-v2
 endef
 TARGET_DEVICES += tl-archer-c7-v2
 
+define Device/tl-re450-v2
+  $(Device/tplink)
+  ATH_SOC := qca9563
+  IMAGE_SIZE := 6016k
+  DEVICE_TITLE := TP-LINK RE450 v2
+  DEVICE_PACKAGES := kmod-ath10k ath10k-firmware-qca988x
+  TPLINK_HWID := 0x0
+  TPLINK_HWREV := 0
+  TPLINK_BOARD_ID := RE450-V2
+  LOADER_TYPE := elf
+  KERNEL := kernel-bin | append-dtb | lzma | tplink-v1-header -O
+  IMAGE/sysupgrade.bin := append-rootfs | tplink-safeloader sysupgrade | \
+    append-metadata | check-size $$$$(IMAGE_SIZE)
+  IMAGE/factory.bin := append-rootfs | tplink-safeloader factory
+  SUPPORTED_DEVICES := tplink,re450-v2
+endef
+TARGET_DEVICES += tl-re450-v2
+
 define Device/tl-wdr3600
   $(Device/tplink-8mlzma)
   ATH_SOC := ar9344