mod_proxy: only cleanup the socket of a connection asked to be closed but

whose address can still be reused.

This saves unnecessary socket pool destroy and creation at cleanup and reuse
time, plus the same initialization of conn->pool's associated data which can
be reused in that case.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1678763 13f79535-47bb-0310-9956-ffa450edef68