Fix segfault when restarting worker MPM. We can not examine the POD as

Fix segfault when restarting worker MPM.  We can not examine the POD as
a normal listener.

There was an additional bug than what Ian submitted to fix listen.c
(i.e. check sa for null): make_pipe_of_death does not zero out
lr->bind_addr (since it uses apr_palloc).  So, on Solaris, the first
time through, bind_addr was probably 0, but the second time, not (pools!).
(This caused Aaron's analysis that the patch worked the first time,
but not the second time.)

Submitted by:	Ian Holsman
Reviewed by:	Justin Erenkrantz, Aaron Bannert

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@92387 13f79535-47bb-0310-9956-ffa450edef68