[Perl/perl5] b73cad: ext/POSIX/t/sysconf.t: only unlink the fifo if we ...

[Tony Cook via perl5-changes]

  Branch: refs/heads/blead
  Home:   https://github.com/Perl/perl5
  Commit: b73caddf6779a7f7c36ca44e496b2b9498c657de
      
https://github.com/Perl/perl5/commit/b73caddf6779a7f7c36ca44e496b2b9498c657de
  Author: Tony Cook <t...@develop-help.com>
  Date:   2020-11-04 (Wed, 04 Nov 2020)

  Changed paths:
    M ext/POSIX/t/sysconf.t

  Log Message:
  -----------
  ext/POSIX/t/sysconf.t: only unlink the fifo if we have a name for it

This warned on Win32 since the whole test file is skipped due
to the lack of anything sysconf() to test.