Exit when we can't listen on any of the configured ports. This

is the same behavior as 1.3, and it avoids having the MPMs to
deal with bogus ap_listen_rec structures.

This also backs out some circumventions I and Greg Ames had added
to prefork; these are no longer necessary because of this change.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@91494 13f79535-47bb-0310-9956-ffa450edef68