bug#6581: 24.0.50; `equal-including-properties' uses `eq' to compare property values

[Eli Zaretskii]

> From: Stefan Kangas <stefan@marxist.se>
> Date: Thu, 21 Oct 2021 11:05:57 -0700
> Cc: 6581@debbugs.gnu.org, Christian Ohler <ohler+emacs@fastmail.net>,
>  Dmitry Gutov <dgutov@yandex.ru>
> 
> I hope that Eli or Lars could say if they prefer the first patch (with
> the bug fix) on emacs-28 or master.

On master, please.  It's not really a bugfix, it's a kind-of
enhancement, and the change is not trivial.

Thanks.