usb: Change usb_hcd->bandwidth_mutex to a pointer.

Change the bandwith_mutex in struct usb_hcd to a pointer.  This will allow
the pointer to be shared across usb_hcds for the upcoming work to split
the xHCI driver roothub into a USB 2.0/1.1 and a USB 3.0 bus.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h
index 0be6197..836aaa9 100644
--- a/include/linux/usb/hcd.h
+++ b/include/linux/usb/hcd.h
@@ -142,7 +142,7 @@
 	 * bandwidth_mutex should be dropped after a successful control message
 	 * to the device, or resetting the bandwidth after a failed attempt.
 	 */
-	struct mutex		bandwidth_mutex;
+	struct mutex		*bandwidth_mutex;
 
 
 #define HCD_BUFFER_POOLS	4