[PATCH] usb: fix uss720 schedule with interrupts off

This patch fixes the long standing schedule with interrupts off problem
of the uss720 driver. The problem is caused by the parport layer calling
the save and restore methods within a write_lock_irqsave guarded region.
The fix is to issue the control transaction requests required by save
and restore asynchronously.

Signed-off-by: Thomas Sailer, <sailer@ife.ee.ethz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>