disconnect handling misdesigned on uss720

Hi,

looking at this:

static unsigned int kill_all_async_requests_priv(struct parport_uss720_private *priv)
{
         struct uss720_async_request *rq;
         unsigned long flags;
         unsigned int ret = 0;

         spin_lock_irqsave(&priv->asynclock, flags);
         list_for_each_entry(rq, &priv->asynclist, asynclist) {
                 usb_unlink_urb(rq->urb);
                 ret++;
         }
         spin_unlock_irqrestore(&priv->asynclock, flags);
         return ret;
}

it seems to me that this is a broken design.
It uses only usb_unlink_urb() but does not wait for the actual
unlink. It seems to me that we need to count them and _wait_
for the count to reach 0.

What do you think?

	Regards
		Oliver