bug#55635: `make-decoded-time' incorrectly sets DST to nil, it should be -1 (guess)

[Eli Zaretskii]

> Cc: 55635-done@debbugs.gnu.org
> From: Maxim Nikulin <m.a.nikulin@gmail.com>
> Date: Sat, 28 May 2022 23:31:43 +0700
> 
> I think, it is confusing that `make-decoded-time' is used to create 
> timestamps *and* time intervals. They are different types, for example 
> sum of intervals is meaningful (despite may be ambiguous) while there is 
> no point to add timestamps.

But this situation already exists with time units anyway.  You can add
an hour to some other time, but there's also a valid time stamp that
expresses 1 hour past the epoch UTC, and their values are exactly
identical.