When firing up a new child process, wipe clean the set of worker_score records

we're going to use as they could contain leftovers from a previous child.
This solves a problem where a non-graceful restart followed by a graceful
restart would leave previous generation children stuck waiting for non-existant
worker threads to terminate.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@93548 13f79535-47bb-0310-9956-ffa450edef68