USB: unkill cxacru atm driver

it seems like you overdid it a bit in your quest to clean up the
use of urb->status. In this driver you read it the first thing, which
means that you are in a race against URB completion you'll
usually lose, returning -EINPROGRESS. This kills the driver.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>