usb: host: add dependence for USB_EHCI_MV

This ehci driver is mainly designed to support host controller found on
Marvell PXA and MMP Soc series.
Add the dependence to avoid the potential build failure which may
include two EHCI controller drivers.

Signed-off-by: Neil Zhang <zhangwm@marvell.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/Kconfig

@@ -196,7 +196,7 @@ config USB_EHCI_S5P
 
 config USB_EHCI_MV
 	bool "EHCI support for Marvell on-chip controller"
-	depends on USB_EHCI_HCD
+	depends on USB_EHCI_HCD && (ARCH_PXA || ARCH_MMP)
 	select USB_EHCI_ROOT_HUB_TT
 	---help---
 	  Enables support for Marvell (including PXA and MMP series) on-chip