[Perl/perl5] 5ee777: Don't use POSIX 2008 locales on cygwin

[Karl Williamson via perl5-changes]

  Branch: refs/heads/blead
  Home:   https://github.com/Perl/perl5
  Commit: 5ee7770b70fd48652f905014e47b07eb031ed5bc
      
https://github.com/Perl/perl5/commit/5ee7770b70fd48652f905014e47b07eb031ed5bc
  Author: Karl Williamson <k...@cpan.org>
  Date:   2022-08-11 (Thu, 11 Aug 2022)

  Changed paths:
    M cygwin/cygwin.c
    M hints/cygwin.sh

  Log Message:
  -----------
  Don't use POSIX 2008 locales on cygwin

newlocale(), required for this, is buggy. See
https://sourceware.org/pipermail/cygwin/2022-August/252043.html