USB: EHCI: make ehci-vt8500 a separate driver

With the multiplatform changes in arm-soc tree, it becomes
possible to enable the vt8500 platform at the same time
as other platforms that require a conflicting EHCI bus
glue. At the moment, this results in a warning like

drivers/usb/host/ehci-hcd.c:1277:0: warning: "PLATFORM_DRIVER" redefined [enabled by default]
drivers/usb/host/ehci-hcd.c:1257:0: note: this is the location of the previous definition
drivers/usb/host/ehci-omap.c:319:31: warning: 'ehci_hcd_omap_driver' defined but not used [-Wunused-variable]

and an ehci driver that only works on one of them.

With the infrastructure added by Alan Stern in patch 3e0232039
"USB: EHCI: prepare to make ehci-hcd a library module", we can
avoid this problem by turning a bus glue into a separate
module, as we do here for the vt8500 bus glue.

Signed-off-by: Manjunath Goudar <manjunath.goudar@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Tony Prisk <linux@prisktech.co.nz>
Cc: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index c59a112..d77e028 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -162,6 +162,14 @@
 	  Enables support for the on-chip EHCI controller on
 	  OMAP3 and later chips.
 
+config USB_EHCI_HCD_VT8500
+        tristate "Support for VT8500 on-chip EHCI USB controller"
+        depends on USB_EHCI_HCD && ARCH_VT8500
+        default y
+        ---help---
+          Enables support for the on-chip EHCI controller on
+          VT8500 chips.
+
 config USB_EHCI_MSM
 	bool "Support for MSM on-chip EHCI USB controller"
 	depends on USB_EHCI_HCD && ARCH_MSM