with various udev-event tools which wrongly scan and open
internal temporary cryptsetup devices.
If cryptsetup run in debug mode (--debug) and remove of device
fails, code scan /proc directory and tries to find process name
which locked that device.
git-svn-id: https://cryptsetup.googlecode.com/svn/trunk@141 36d66b0a-2a48-0410-832c-cd162a569da5