usb-uhci: update irq line on reset

uhci_reset() clears irq mask and irq status registers, but doesn't
update the irq line.  Which may result in suspious IRQs after uhci
reset.  Fix it.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

hw/usb/hcd-uhci.c

@@ -369,6 +369,7 @@ static void uhci_reset(void *opaque)
     }
 
     uhci_async_cancel_all(s);
+    uhci_update_irq(s);
 }
 
 static void uhci_pre_save(void *opaque)