Changes:
  * Re-add the 'dev->fd = fd;' line which the qdev patches dropped
    by mistake.
  * call qdev_init() so the newly created usb device is plugged into
    a usb port and thus actually visible to the guest.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>