mod_ldap: Change the LDAP connection timeout to per-connection rather than global. Fixes PR: 34618

Reviewed by: bnicholes, minfrin, pquerna

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.0.x@170805 13f79535-47bb-0310-9956-ffa450edef68