bug#42753: 26.3; `info-lookup.el': Add all manuals delivered by `emacs -Q', for `emacs-lisp-mode'

[Eli Zaretskii]

> From: Michael Albinus <michael.albinus@gmx.de>
> Cc: larsi@gnus.org,  42753@debbugs.gnu.org,  drew.adams@oracle.com
> Date: Fri, 08 Oct 2021 18:23:38 +0200
> 
> > I think a better solution will be to be tolerant, i.e. look for nodes
> > that contain "index", and maybe also "function" or "variable", in them
> > regardless of the rest.
> 
> Sure. Same for *ELPA manuals. But I believe we also should use some
> conventions for manuals under our control.

That should be a Good Thing regardless.