ath79: add support for NEC Aterm WG1200CR

NEC Aterm WG1200CR is a 2.4/5 GHz band 11ac router,
based on Qualcomm Atheros QCA9563.

Specification:

- SoC		: Qualcomm Atheros QCA9563
- RAM		: DDR2 128 MiB
- Flash		: SPI-NOR 8 MiB
- WLAN		: 2.4/5 GHz 2T2R
  - 2.4 GHz	: QCA9563 (SoC)
  - 5 GHz	: QCA9888
- Ethernet	: 2x 10/100/1000 Mbps
  - Switch	: QCA8334
- LEDs/Input	: 12x/4x (2x buttons, 1x slide-switch)
- UART		: through-hole on PCB
  - JP1: Vcc, GND, NC, TX, RX from power connector side
  - 115200 bps

Flash instruction using factory image:

1. Boot WG1200CR normaly
2. Access to "http://192.168.10.1/" and open firmware update page
("ファームウェア更新")
3. Select the OpenWrt factory image and click update ("更新") button
to perform firmware update
4. Wait ~150 seconds to complete flashing

Known issues:

- cannot be controlled LEDs other than Power (Green/Red)
  - only Power LEDs are connected to SoC GPIO; other LEDs
    connected to the gpiochip on ath10k chip (QCA9888)

Signed-off-by: INAGAKI Hiroshi <musashino.open@gmail.com>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com> [commit
message formatting]

target/linux/ath79/image/generic.mk

@@ -42,6 +42,12 @@ define Build/add-elecom-factory-initramfs
   fi
 endef
 
+define Build/nec-enc
+  $(STAGING_DIR_HOST)/bin/nec-enc \
+    -i $@ -o $@.new -k $(1)
+  mv $@.new $@
+endef
+
 define Build/nec-fw
   ( stat -c%s $@ | tr -d "\n" | dd bs=16 count=1 conv=sync; ) >> $@
   ( \
@@ -446,6 +452,24 @@ define Device/librerouter_librerouter-v1
 endef
 TARGET_DEVICES += librerouter_librerouter-v1
 
+define Device/nec_wg1200cr
+  ATH_SOC := qca9563
+  DEVICE_TITLE := NEC Aterm WG1200CR
+  IMAGE_SIZE := 7616k
+  SEAMA_MTDBLOCK := 6
+  SEAMA_SIGNATURE := wrgac72_necpf.2016gui_wg1200cr
+  IMAGES += factory.bin
+  IMAGE/default := \
+    append-kernel | pad-offset $$$$(BLOCKSIZE) 64 | append-rootfs
+  IMAGE/sysupgrade.bin := \
+    $$(IMAGE/default) | seama | pad-rootfs | append-metadata | check-size $$$$(IMAGE_SIZE)
+  IMAGE/factory.bin := \
+    $$(IMAGE/default) | pad-rootfs -x 64 | seama | seama-seal | nec-enc 9gsiy9nzep452pad | \
+    check-size $$$$(IMAGE_SIZE)
+  DEVICE_PACKAGES := kmod-ath10k-ct ath10k-firmware-qca9888-ct
+endef
+TARGET_DEVICES += nec_wg1200cr
+
 define Device/nec_wg800hp
   ATH_SOC := qca9563
   DEVICE_TITLE := NEC Aterm WG800HP