MIPS: ath79: Add config symbol for the AR933X SoCs

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: Kathy Giori <kgiori@qca.qualcomm.com>
Cc: "Luis R.  Rodriguez" <rodrigue@qca.qualcomm.com>
Patchwork: https://patchwork.linux-mips.org/patch/2525/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/ath79/Kconfig

@@ -41,6 +41,9 @@ config SOC_AR913X
 	select USB_ARCH_HAS_EHCI
 	def_bool n
 
+config SOC_AR933X
+	def_bool n
+
 config ATH79_DEV_AR913X_WMAC
 	depends on SOC_AR913X
 	def_bool n