tree-wide: Drop custom formatting for print() help messages

tree-wide: Drop custom formatting for print() help messages

I think this formatting was originally used because it simplified
adding new options to the help messages. However, these days, most
tools their help message end with "\nSee the %s for details.\n" so
the final line almost never has to be edited which eliminates the
benefit of the custom formatting used for printf() help messages.
Let's make things more consistent and use the same formatting for
printf() help messages that we use everywhere else.

Prompted by https://github.com/systemd/systemd/pull/18355#discussion_r567241580