Doc fixes

Doc fixes

* doc/misc/autotype.texi (Skeleton Language):
* doc/misc/message.texi (Header Commands):
* lisp/allout-widgets.el (allout-widgets-tally)
(allout-decorate-item-guides):
* lisp/menu-bar.el (menu-bar-positive-p):
* lisp/minibuffer.el (completion-pcm-complete-word-inserts-delimiters):
* lisp/cedet/ede.el (ede-project-directories, ede-check-project-directory):
* lisp/cedet/semantic/ia-sb.el (semantic-ia-sb-show-doc):
* lisp/cedet/semantic/tag.el (semantic-tag-in-buffer-p):
* lisp/cedet/semantic/bovine/c.el (semantic-tag-abstract-p):
* lisp/gnus/gnus-registry.el (gnus-registry-install-p): Doc fix.
* lisp/progmodes/gdb-mi.el (gdbmi-same-start, gdbmi-is-number):
* lisp/progmodes/js.el (js--inside-param-list-p)
(js--inside-dojo-class-list-p, js--forward-destructuring-spec):
* lisp/progmodes/prolog.el (region-exists-p):
* lisp/progmodes/verilog-mode.el (verilog-scan-cache-ok-p):
* lisp/textmodes/reftex-parse.el (reftex-using-biblatex-p):
* lisp/url/url-parse.el (url-generic-parse-url):
* src/floatfns.c (Fisnan):
* src/profiler.c (Fprofiler_cpu_running_p):
Doc fixes (replace `iff').

Fixes: debbugs:17309