Get the perchild MPM building cleanly again. This hasn't been tested,

because I can't install Apache right now.  As soon as I get the make
install target working, I'll test this MPM.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@87224 13f79535-47bb-0310-9956-ffa450edef68