bug#64045: [PATCH] Improve wording of the documentation about declare form

[Eli Zaretskii]

> From: Shynur Xie <one.last.kiss@outlook.com>
> Date: Tue, 13 Jun 2023 13:36:50 +0000
> msip_labels: 
> 
> I modified section 13.14 (The declare form) of the GNU Emacs Lisp
> Reference Manual.  The manual didn't say how to make
> 
>     (declare (completion ...)
>              (modes ...))
> 
> take effect; the original text is even somewhat misleading.  Simply
> evaluating a (defun ...) form which includes the above declare form
> won't make Emacs filter commands when asking for completion in M-x.

Thanks, but the text you suggest reads as more complex and harder to
understand.  So how about explaining what was wrong or missing or
unclear in the original text?  Then I could come up with a better
wording.