[Perl/perl5] e0748e: locale.c: C is the only locale under NO_LOCALE

[Karl Williamson via perl5-changes]

  Branch: refs/heads/blead
  Home:   https://github.com/Perl/perl5
  Commit: e0748e831ac8161a2a2e1c67162330c025ddb2e7
      
https://github.com/Perl/perl5/commit/e0748e831ac8161a2a2e1c67162330c025ddb2e7
  Author: Karl Williamson <k...@cpan.org>
  Date:   2024-01-02 (Tue, 02 Jan 2024)

  Changed paths:
    M locale.c

  Log Message:
  -----------
  locale.c: C is the only locale under NO_LOCALE

It is possible to Configure perl to not pay attention to locales at all.
Effectively that means the only permissible locale is "C", which
underlies all C programs at startup.

Thus, when asked what the current locale is, the answer is always going
to be "C"; and we can define the macro that computes this info to just
return "C" instead of doing any lookup.