All man pages refer to FreeBSD so there is no need to mention "In .Fx"
Mention in login.conf.5 which fields may be infinite and how to specifify infinity.
The number of ways to indicate this confuses people.

PR:		docs/100196
Reported by:	"Dr. Markus Waldeck" <waldeck@gmx.de>
Reported by:	Jamie Landeg Jones <jamie.landeg.jones@gmail.com>