mediatek: add support for Buffalo WSR-3200AX4S

Buffalo WSR-3200AX4S is a 2.4/5 GHz band 11ax (Wi-Fi 6) router, based on
MT7622B.

Specification:

- SoC         : MediaTek MT7622B
- RAM         : DDR3 512 MiB
- Flash       : SPI-NAND 128 MiB (Winbond W25N01GVZEIG)
- WLAN        : 2.4/5 GHz 4T4R
  - 2.4 GHz   : MediaTek MT7622B (SoC)
  - 5 GHz     : MediaTek MT7915
- Ethernet    : 5x 10/100/1000 Mbps
  - Switch    : MediaTek MT7531
- LEDs/Keys   : 6x/5x (2x: buttons, 3x: slide-switches)
- UART        : through-hole on PCB (J4)
  - assignment: 3.3V, GND, TX, RX from tri-angle marking
  - settings  : 115200n8
- Power       : 12 VDC, 1.5 A

Flash instruction using factory.bin image:

1. Boot WSR-3200AX4S with "Router" mode
2. Access to "http://192.168.11.1/" and open firmware update page
   ("ファームウェア更新")
3. Select the OpenWrt factory.bin image and click update ("更新実行")
   button
4. Wait ~120 seconds to complete flashing

Note:

- This device has 2x OS images on flash. The first one will always be
  used for booting and the secondary is for backup.

- This support generates multiple factory*.bin image:

  - factory.bin      : for flashing from OEM WebUI
  - factory-uboot.bin: for flashing from U-Boot or clean installation
                       via sysupgrade (don't use for normal sysupgrade)

Known issues:

- Wi-Fi MAC addresses won't be applied to each adapter.

MAC Addresses:

LAN    : C4:3C:EA:xx:xx:60 (board_data, mac (text))
WAN    : C4:3C:EA:xx:xx:60 (board_data, mac (text))
2.4 GHz: C4:3C:EA:xx:xx:61
5 GHz  : C4:3C:EA:xx:xx:68

Signed-off-by: INAGAKI Hiroshi <musashino.open@gmail.com>
(cherry picked from commit 7383eb266b)

target/linux/mediatek/image/mt7622.mk

@@ -128,6 +128,37 @@ define Device/buffalo_wsr-2533dhp2
 endef
 TARGET_DEVICES += buffalo_wsr-2533dhp2
 
+define Device/buffalo_wsr-3200ax4s
+  DEVICE_VENDOR := Buffalo
+  DEVICE_MODEL := WSR-3200AX4S
+  DEVICE_DTS := mt7622-buffalo-wsr-3200ax4s
+  IMAGE_SIZE := 24576k
+  BUFFALO_TRX_MAGIC := 0x33504844
+  DEVICE_PACKAGES := kmod-mt7915-firmware
+  DEVICE_DTS_DIR := ../dts
+  KERNEL_SIZE := 6144k
+  BLOCKSIZE := 128k
+  PAGESIZE := 2048
+  UBINIZE_OPTS := -E 5
+  BUFFALO_TAG_PLATFORM := MTK
+  BUFFALO_TAG_VERSION := 9.99
+  BUFFALO_TAG_MINOR := 9.99
+  IMAGES += factory.bin factory-uboot.bin
+  KERNEL_INITRAMFS = kernel-bin | lzma | \
+	fit lzma $$(KDIR)/image-$$(firstword $$(DEVICE_DTS)).dtb with-initrd | \
+	buffalo-trx
+  IMAGE/factory.bin = append-ubi | \
+	buffalo-trx $$$$(BUFFALO_TRX_MAGIC) $$$$@ $(KDIR)/ubi_mark | \
+	buffalo-enc $$(DEVICE_MODEL) $$(BUFFALO_TAG_VERSION) -l | \
+	buffalo-tag-dhp $$(DEVICE_MODEL) JP JP | buffalo-enc-tag -l | buffalo-dhp-image
+  IMAGE/factory-uboot.bin := append-ubi | \
+	buffalo-trx $$$$(BUFFALO_TRX_MAGIC) $$$$@ $(KDIR)/ubi_mark
+  IMAGE/sysupgrade.bin := \
+	buffalo-trx $$$$(BUFFALO_TRX_MAGIC) $(KDIR)/tmp/$$(DEVICE_NAME).null | \
+	sysupgrade-tar kernel=$$$$@ | append-metadata
+endef
+TARGET_DEVICES += buffalo_wsr-3200ax4s
+
 define Device/elecom_wrc-2533gent
   DEVICE_VENDOR := Elecom
   DEVICE_MODEL := WRC-2533GENT