This really only makes sense if we are running systemd as PID1
inside the container, but we are not booting a system, just using
it as a glorified chroot.
This means entering the namespaces from the outside will be a bit
more cumbersome, but that was not used much and was never reliable
to begin with.
Signed-off-by: Tom Gundersen <teg@jklm.no>
Add a directory to each BuildRoot potentially containing a set of
sockets. Also add a helper to create a named bound socket in a given
BuildRoot.
Signed-off-by: Tom Gundersen <teg@jklm.no>
