ath79: add support for Qihoo C301

Specifications:
- SoC: AR9344
- RAM: 128MB
- Flash: 2 * 16MB (MX25L12845)
- Ethernet: 2 * FE LAN & 1 * FE WAN
- WiFi: 2.4G: AR9344 5G: QCA9882

Flash instruction:
1. Hold reset and power up the router
2. Set your IP to 192.168.1.x
3. Open 192.168.1.1 and upload the generated *factory* firmware

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

target/linux/ath79/base-files/etc/init.d/bootcount

@@ -0,0 +1,11 @@
+#!/bin/sh /etc/rc.common
+START=99
+
+boot() {
+	case $(board_name) in
+	qihoo,c301)
+		local n=$(fw_printenv activeregion | cut -d = -f 2)
+		fw_setenv "image${n}trynum" 0
+		;;
+	esac
+}