Support GD32F103.

src/usb-ccid.c

@@ -1579,6 +1579,10 @@ usb_event_handle (struct usb_dev *dev)
   /* Transfer to endpoint (not control endpoint) */
   if (ep_num != 0)
     {
+      /* Ignore sprious "Correct Transfer" */
+      if (bDeviceState != USB_DEVICE_STATE_CONFIGURED)
+	return 0;
+
       if (USB_EVENT_TXRX (e))
 	usb_tx_done (ep_num, USB_EVENT_LEN (e));
       else