bug#57432: 27.1; doc-view-enlarge/shrink behaviour does not match documentation

[Lars Ingebrigtsen]

Iago <iago.gine@sjd.es> writes:

> I read this in the DocView documentation as it appears when typing
> 'C-h m' in the DocView mode.

In Emacs 27.1, this says:

key             binding
---             -------

C-c             Prefix Command
RET             image-next-line
C-n             doc-view-next-line-or-next-page
C-p             doc-view-previous-line-or-previous-page
C-r             doc-view-search-backward
C-s             doc-view-search
C-t             doc-view-show-tooltip
ESC             Prefix Command
SPC             doc-view-scroll-up-or-next-page
+               doc-view-enlarge
-               doc-view-shrink

This does not mean that `C-c' is the prefix key for all the stuff
that's underneath it -- it just means that `C-c' is a prefix command
(and is unrelated to the stuff below).

This display has been changed in Emacs 29 -- we don't mention the prefix
commands at all, because that brings no value.