Fix bug found when building on an IPv6-only system by Kai Blin.

Fix bug found when building on an IPv6-only system by Kai Blin.

When building on IPv6-only, doing:

hints.ai_family = AF_INET;
getaddrinfo("0.0.0.0", NULL, &hints, &ppres)

fails as AF_INET is unavailable on an IPv6-only system. This
causes us to fallback to our replacement getaddrinfo code
which is IPv4-only.

As we're only trying to detect a specific AIX bug here,
broaden the tests to find that bug, and also test for
working getaddrinfo in an IPv6-only safe way.

Autobuild-User: Jeremy Allison <jra@samba.org>
Autobuild-Date: Thu May 19 02:21:54 CEST 2011 on sn-devel-104