tmpfiles: fix typo in error message

tmpfiles: fix typo in error message

Fixes #4097.

As of current master, systemd-tmpfiles behaves correctly, apart from a trivial
typo. So let's tell github to close the bug.

With current git:

$ sudo SYSTEMD_LOG_LEVEL=debug build/systemd-tmpfiles --create `pwd`/test/tmpfiles.d/link-loop.conf
Successfully loaded SELinux database in 2.385ms, size on heap is 321K.
Reading config file "/home/zbyszek/src/systemd-work/test/tmpfiles.d/link-loop.conf".
Running create action for entry D /run/hello2
Found existing directory "/run/hello2".
"/run/hello2" has right mode 41777
Running create action for entry f /run/hello2/hello2.test
"/run/hello2/hello2.test" has been created.
"/run/hello2/hello2.test" has right mode 101777
chown "/run/hello2/hello2.test" to 0.84
Running create action for entry L /run/hello2/hello2.link
Found existing symlink "/run/hello2/hello2.link".
Running create action for entry z /run/hello2/hello2.test
"/run/hello2/hello2.test" has right mode 101777
chown "/run/hello2/hello2.test" to 0.0
Running create action for entry z /run/hello2/hello2.link
Skipping mode an owner fix for symlink /run/hello2/hello2.link.

and the permissions are:
$ ls -dl /run/hello2/ /run/hello2/*
drwxrwxrwt. 2 foo   bar    80 Nov 22 14:40 /run/hello2/
lrwxrwxrwx. 1 root  root   23 Nov 22 14:40 /run/hello2/hello2.link -> /run/hello2/hello2.test
-rwxrwxrwt. 1 root  root    0 Nov 22 14:40 /run/hello2/hello2.test

Everything seems correct.