bug#42095: 28.0.50; Build fails on Windows/MinGW64

[Eli Zaretskii]

> Cc: peder@klingenberg.no, 42095@debbugs.gnu.org
> From: Paul Eggert <eggert@cs.ucla.edu>
> Date: Sun, 28 Jun 2020 23:56:44 -0700
> 
> On 6/28/20 7:28 PM, Eli Zaretskii wrote:
> > I just wanted something to cause the call to getrandom, just to see it
> > working and producing some reasonable value.  Would that be easy to
> > arrange?
> 
> If all we want to do is call getrandom, the Gnulib module 'getrandom-tests' 
> does
> that.

I meant to make sure it works when invoked from Emacs.  Sorry for not
making that clear.