USB: ehci: add bus glue for the Atheros AR71XX/AR724X/AR91XX SoCs

The Atheros AR71XX/AR91XX SoCs have a built-in EHCI controller.
This patch adds the necessary glue code to make the generic EHCI
driver usable for them.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Imre Kaloz <kaloz@openwrt.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/arch/mips/ath79/Kconfig b/arch/mips/ath79/Kconfig
index b058282..649a2a3 100644
--- a/arch/mips/ath79/Kconfig
+++ b/arch/mips/ath79/Kconfig
@@ -26,12 +26,15 @@
 endmenu
 
 config SOC_AR71XX
+	select USB_ARCH_HAS_EHCI
 	def_bool n
 
 config SOC_AR724X
+	select USB_ARCH_HAS_EHCI
 	def_bool n
 
 config SOC_AR913X
+	select USB_ARCH_HAS_EHCI
 	def_bool n
 
 config ATH79_DEV_AR913X_WMAC