bug#32803: 26.1.50; cl-do: Add more literature in docstring

[Eli Zaretskii]

> From: Eric Abrahamsen <eric@ericabrahamsen.net>
> Cc: Eli Zaretskii <eliz@gnu.org>,  32803@debbugs.gnu.org
> Date: Mon, 24 Sep 2018 09:43:49 -0700
> 
> > +Then, in each iteration of the loop, the END-TEST is evaluated; if true,
>          ^^^^^^^
> 
> >From the peanut gallery: Without looking at the code, I'm not sure if
> this means the test is evaluated *before* BODY (ie, BODY may never run),
> or *after* BODY (ie, BODY always runs at least once).

You've removed the answer to that question.  The full text says:

                                                          Then, in each
     iteration of the loop, the END-TEST is evaluated; if true, the loop
     is finished.  Otherwise, the body FORMS are evaluated, then each
     VAR is set to the associated STEP expression [...]

which clearly tells that the test is done _before_ the BODY is run.
Right?