[Perl/perl5] 55c938: Fix CCHOME setting for MinGW

[Max Maischein]

  Branch: refs/heads/blead
  Home:   https://github.com/Perl/perl5
  Commit: 55c93881eb6a175f7f74fdb482dfe22173f67747
      
https://github.com/Perl/perl5/commit/55c93881eb6a175f7f74fdb482dfe22173f67747
  Author: Max Maischein <cor...@corion.net>
  Date:   2019-11-18 (Mon, 18 Nov 2019)

  Changed paths:
    M .github/workflows/smoke-windows-mingw64.yml

  Log Message:
  -----------
  Fix CCHOME setting for MinGW