Cleanup uses of "-hooks".

Cleanup uses of "-hooks".
* doc/emacs/custom.texi (Hooks):
* doc/lispref/hooks.texi (Standard Hooks): Clarify that -hooks is deprecated.

* lisp/gnus/nndiary.el (nndiary-request-create-group-functions)
(nndiary-request-update-info-functions)
(nndiary-request-accept-article-functions):
* lisp/gnus/gnus-start.el (gnus-subscribe-newsgroup-functions):
* lisp/cedet/semantic/db-file.el (semanticdb-save-database-functions):
* lisp/cedet/semantic/lex.el (semantic-lex-reset-functions):
* lisp/cedet/semantic/edit.el (semantic-change-functions)
(semantic-edits-new-change-functions)
(semantic-edits-delete-change-functions)
(semantic-edits-reparse-change-functions):
* lisp/htmlfontify.el (hfy-post-html-hook):
* lisp/filesets.el (filesets-cache-fill-content-hook):
* lisp/arc-mode.el (archive-extract-hook):
* lisp/progmodes/cc-mode.el (c-prepare-bug-report-hook):
* lisp/net/rcirc.el (rcirc-sentinel-functions)
(rcirc-receive-message-functions, rcirc-activity-functions)
(rcirc-print-functions):
* lisp/net/dbus.el (dbus-event-error-functions):
* lisp/emacs-lisp/eieio.el (eieio-pre-method-execution-functions):
* lisp/emacs-lisp/checkdoc.el (checkdoc-style-functions)
(checkdoc-comment-style-functions): Don't use "-hooks" suffix.

* lisp/term/sun.el (sun-raw-prefix-hooks):
* lisp/mail/sendmail.el (mail-yank-hooks):
* lisp/mh-e/mh-letter.el (mh-yank-hooks): Use make-obsolete-variable.