USB: FIx locks and urb->status in adutux (updated)
Two main issues fixed here are:
- An improper use of in-struct lock to protect an open count
- Use of urb status for -EINPROGRESS
Also, along the way:
- Change usb_unlink_urb to usb_kill_urb. Apparently there's no need
to use usb_unlink_urb whatsoever in this driver, and the old use of
usb_kill_urb was outright racy (it unlinked and immediately freed).
- Fix indentation in adu_write. Looks like it was damaged by a script.
- Vitaly wants -EBUSY on multiply opens.
- bInterval was taken from a wrong endpoint.