Merge r1351737 from trunk:

* support/ab.c (test, start_connect): Only bind the local end of the
  socket (and look up an address for it) if -B is specified.

Reviewed by: trawick, rjung, jorton


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1364674 13f79535-47bb-0310-9956-ffa450edef68