Fix a kernel crash for bulk devices when closing the video stream; We give the kthread loop a moment to recognize that bulk_running=0 before we close the USB pipes.  Otherwise it can happen that we close the USB pipes before the kthread loop stopped.
Fix a kernel crash for bulk devices when closing the video stream;
We give the kthread loop a moment to recognize that bulk_running=0
before we close the USB pipes.  Otherwise it can happen that we close
the USB pipes before the kthread loop stopped.

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars