Correct failure with Listen directives on machines with IPv6 enabled by

Correct failure with Listen directives on machines with IPv6 enabled by
removing find_default_family() and letting APR determine what should be done
without a hostname.

This patch requires the corollary APR patch to properly call getaddrinfo().

(Justin modified Colm's patch to always walk the old listeners even when
we have an address.  That part of the patch wasn't really relevant.)

Submitted by:	Colm MacC�rthaigh <colm@stdlib.net>
Reviewed by:	Justin Erenkrantz

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@100978 13f79535-47bb-0310-9956-ffa450edef68