[Perl/perl5] 07a53d: win32/GNUmakefile: only use gcc warnings for the p...

[Tony Cook via perl5-changes]

  Branch: refs/heads/blead
  Home:   https://github.com/Perl/perl5
  Commit: 07a53dca6ee0b9c82acfb8d777fe4e7cc6aae661
      
https://github.com/Perl/perl5/commit/07a53dca6ee0b9c82acfb8d777fe4e7cc6aae661
  Author: Tony Cook <t...@develop-help.com>
  Date:   2024-02-05 (Mon, 05 Feb 2024)

  Changed paths:
    M win32/GNUmakefile

  Log Message:
  -----------
  win32/GNUmakefile: only use gcc warnings for the perl binary sources

Fixes #21873