This will be used to create a communication pipe between the user
facing device and a freshly forked (per pipeline compile) slim copy
of that device.
We can't use pipe() here because the fork will not be a direct fork
of the user facing process. Instead we use a previously forked
copy of the process that was forked at device creation in order to
reduce the resources required for the fork and avoid performance
issues.
Fixes: cff53da374 ("radv: enable secure compile support")
1663bb1f77