/run/utmp is already in systemd's default config, with proper flags
(boot only) and permissions, and /var/run is a symlink to /run as
per systemd standard so we don't need to list /var/run/utmp in
busybox's tmpfiles list.
This also removes these systemd boot warnings
Line references path below legacy directory /var/run/
Duplicate line for path "/run/utmp", ignoring.
Signed-off-by: Matthias Reichl <hias@horus.com>