mips: ath79: add support for AR933x SOCs

This patch enable work for ar933x SOC.

Signed-off-by: Wills Wang <wills.wang@live.com>
diff --git a/arch/mips/mach-ath79/Kconfig b/arch/mips/mach-ath79/Kconfig
index 7d8ce09..ab93d92 100644
--- a/arch/mips/mach-ath79/Kconfig
+++ b/arch/mips/mach-ath79/Kconfig
@@ -4,4 +4,13 @@
 config SYS_SOC
 	default "ath79"
 
+config SOC_AR933X
+	bool
+	select SUPPORTS_BIG_ENDIAN
+	select SUPPORTS_CPU_MIPS32_R1
+	select SUPPORTS_CPU_MIPS32_R2
+	select MIPS_TUNE_24KC
+	help
+	  This supports QCA/Atheros ar933x family SOCs.
+
 endmenu