Test both 0.0.0.0 and 127.0.0.x addresses to find a usable port.

Test both 0.0.0.0 and 127.0.0.x addresses to find a usable port.

Commit c098509927f9a49ebceb301a2cb6a477ecd4ac3c changed
PostgresNode::get_new_node() to probe 0.0.0.0 instead of 127.0.0.1, but
the new test was less effective for Windows native Perl.  This increased
the failure rate of buildfarm members bowerbird and jacana.  Instead,
test 0.0.0.0 and concrete addresses.  This restores the old level of
defense, but the algorithm is still subject to its longstanding time of
check to time of use race condition.  Back-patch to 9.6, like the
previous change.

Discussion: https://postgr.es/m/GrdLgAdUK9FdyZg8VIcTDKVOkys122ZINEb3CjjoySfGj2KyPiMKTh1zqtRp0TAD7FJ27G-OBB3eplxIB5GhcQH5o8zzGZfp0MuJaXJxVxk=@yesql.se