libpayload: Fix detach_contoller in the USB driver

Fixed usb controllers linked list walking in
detach_controller() function

Change-Id: Ia97c7ec814f75d2b1bfe185f160fb4cd32aa6fdb
Signed-off-by: Anton Kochkov <anton.kochkov@gmail.com>
Reviewed-on: http://review.coreboot.org/1105
Tested-by: build bot (Jenkins)
Reviewed-by: Nico Huber <nico.huber@secunet.com>

payloads/libpayload/drivers/usb/usb.c

@@ -63,6 +63,7 @@ detach_controller (hci_t *controller)
 				it->next = controller->next;
 				return;
 			}
+			it = it->next;
 		}
 	}
 }