Add ap_relieve_child_processess(), a non-infanticidal copy of
ap_reclaim_child_processes(). Allows us to waitpid() each process in the
scoreboard and each "extra" process with a single call.



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@240465 13f79535-47bb-0310-9956-ffa450edef68