[usb/usbehci]

[usb/usbehci]
- Add back WorkItem code but use it for calling the hub drivers callback routine (telling hub driver it needs check port status).
- Add missing break for case URB_FUNCTION_GET_STATUS_FROM_DEVICE.
- RootHubInitNotification: BusContext is the Device Object not the Device Objects Extensions.
- UsbEhci now receives URB_FUNCTION_BULK_OR_INTERRUPT_TRANSFER IN requests,
 which is where we want to be for informing hub driver which port a device has been connected.

svn path=/trunk/; revision=45668