unbreak usb pass-through on linux.
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: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>