usb-host-libusb: set USB_DEV_FLAG_IS_HOST

... like host-{linux,bsd}.c do.

Cc: qemu-stable@nongnu.org
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

hw/usb/host-libusb.c

@@ -895,6 +895,7 @@ static int usb_host_initfn(USBDevice *udev)
     USBHostDevice *s = USB_HOST_DEVICE(udev);
 
     loglevel = s->loglevel;
+    udev->flags |= (1 << USB_DEV_FLAG_IS_HOST);
     udev->auto_attach = 0;
     QTAILQ_INIT(&s->requests);
     QTAILQ_INIT(&s->isorings);