Fixed Bug #68420 listen=9000 listens to ipv6 localhost instead of all addresses

Restore default behavior when no address configured:
Listen on all IPv4 addresses.

At some time we could consider to switch to all IPv6
but this will be a BC break.
Merge branch 'PHP-5.5' into PHP-5.6

* PHP-5.5:
  Fixed Bug #68420 listen=9000 listens to ipv6 localhost instead of all addresses