Remove the proxy_conn_cleanup. The socket will be closed

when the pool is cleared or destroyed by it's own cleanup routine.
Also skip clearing sockets if the workers pool is destroyed, cause
the pool might already be destroyed.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@105059 13f79535-47bb-0310-9956-ffa450edef68