When UseCanonicalName is set to OFF, allow ap_get_server_port to check

r->connection->local_addr->port before defaulting to server->port or
ap_default_port().


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@101519 13f79535-47bb-0310-9956-ffa450edef68