bug#41026: Improve documentation of `makunbound' and `fmakunbound'

[Eli Zaretskii]

> From: Stefan Kangas <stefan@marxist.se>
> Date: Sat, 02 May 2020 17:00:02 +0200
> Cc: 41026@debbugs.gnu.org
> 
> Andreas Schwab <schwab@linux-m68k.org> writes:
> 
> > On Mai 02 2020, Stefan Kangas wrote:
> >
> >> +       doc: /* Make variable SYMBOL's value be void.
> >
> > What's a variable symbol?  Is that the same as a varying symbol?
> 
> The sentence is a bit unwieldy to get right, if you also want to
> include the word "variable".  Is this clearer?
> 
> "Make the value of the variable named SYMBOL be void."

I think the ELisp manual gets it right:

  Empty out the value cell of SYMBOL, making it void as a variable.