tmpfiles.d relies on merging lines for the same file paths, as well as
detecting conflicts between lines for the same file paths. /var/run is a
prominent case that is an alias for /run, any many tmpfiles snippets
refer to paths in /var/run rather than /run currently, which breaks the
conflict detection and merging.
We can't really fix this comprehensively, as doing so would require us
to resolve symlinks early on, but that's precisely not what we want to
do, as tmpfiles is usually run very early on where the paths might not
be fully available yet (in particular as we might likely create them
ourselves).
Hence, let's at least detect and fix this case for the most prominent
case of this ambiguity, and also log explicitly about this, asking users
to fix the snippets in question so that the merging and conflict
detection works properly again.
a2d1fb882c