Bug#1120032: systemd: duplicated line in legacy.conf

[Ralf Jung]

I am also seeing this -- not just in the syslog, but also in the terminal, in 
extra noticeable bold font, every time apt touches systemd.

To make things even more confusing, there's a whole host of reports of this as 
can be seen at <https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1104641> and 
all the duplicates merged into it, that are all closed as "wontfix" without a 
single word of explanation. Surely, a warning indicating a possible 
misconfiguration is worth tracking in some form; a bug-free system would not 
show any such warning.

Kind regards,
Ralf