[InterNetNews/inn] be333a: Use pod2man --guesswork when the option is available

[Julien ÉLIE]

  Branch: refs/heads/2.7
  Home:   https://github.com/InterNetNews/inn
  Commit: be333a5073512131d8ed85f8212d726a67ca2821
      https://github.com/InterNetNews/inn/commit/be333a5073512131d8ed85f8212d726a67ca2821
  Author: Julien ÉLIE <Julien-Elie at users.noreply.github.com>
  Date:   2022-12-24 (Sat, 24 Dec 2022)

  Changed paths:
    M Makefile.global.in
    M configure.ac

  Log Message:
  -----------
  Use pod2man --guesswork when the option is available

New in podlators 5.00 recently published, this option permits disabling
heuristics which prevent some patterns like C<@@NCM> (in perl-nocem man page)
from being converted as expected.