USB: add ehci-ppc-of bus glue (device-tree aware)

This adds device-tree-aware ehci-ppc-of driver.
The code is based on the ehci-ppc-soc driver by
Stefan Roese <sr@denx.de>.

Signed-off-by: Valentine Barshak <vbarshak@ru.mvista.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Stefan Roese <sr@denx.de>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index 9b202d5..1f45aa2 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -85,6 +85,14 @@
 	---help---
 	  Variation of ARC USB block used in some Freescale chips.
 
+config USB_EHCI_HCD_PPC_OF
+	bool "EHCI support for PPC USB controller on OF platform bus"
+	depends on USB_EHCI_HCD && PPC_OF
+	default y
+	---help---
+	  Enables support for the USB controller present on the PowerPC
+	  OpenFirmware platform bus.
+
 config USB_ISP116X_HCD
 	tristate "ISP116X HCD support"
 	depends on USB