hier(7): drop list of /usr/share/doc subdirectories

Several entries are outdated, several new ones are missing. I do not
think there is much value added in maintaining this.

Reviewed by:	imp, emaste
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D40001

share/man/man7/hier.7

@@ -324,39 +324,7 @@ terms, proper names, and jargon
 words from Webster's Second International
 .El
 .It Pa doc/
-miscellaneous documentation;
-source for most of the printed
-.Bx
-manuals (available
-from the USENIX association)
-.Bl -tag -width Fl -compact
-.It Pa FAQ/
-Frequently Asked Questions
-.It Pa IPv6/
-implementation notes for IPv6
-.It Pa es/
-Spanish translations of documents in /usr/share/doc
-.It Pa handbook/
-.Fx
-Handbook
-.It Pa ja/
-Japanese translations of documents in /usr/share/doc
-.It Pa legal/
-License files for vendor supplied firmware files
-.It Pa ncurses/
-HTML documents pertaining to ncurses;
-see
-.Xr ncurses 3
-.It Pa ntp/
-HTML documents pertaining to the Network Time Protocol
-.It Pa ru/
-Russian translations of documents in /usr/share/doc
-.It Pa tutorials/
-.Fx
-tutorials
-.It Pa zh/
-Chinese translations of documents in /usr/share/doc
-.El
+miscellaneous documentation
 .It Pa examples/
 various examples for users and programmers
 .It Pa firmware/