* server/mpm/prefork/prefork.c (child_main): Don't log errors for an

  apr_pollset_add() failure if a graceful-stop has been signalled.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1387633 13f79535-47bb-0310-9956-ffa450edef68