In SYS#659 we wanted that "file" will always log to a persistent
/var/log. After I changed the /etc/default/volatiles/00_core for
the IDU and made journald persistent we still ended up having the
symlink. It appears to be caused by this script.
* When "buffer" is used we don't need to care about /var/log as
it is not being used at all.
* When "file" is set we make sure that /var/log is not a symlink.
In case of the IDU the journald should now be persistent.
Related: SYS#659
8b5f88e80b