Log a warning when the LDAP authn provider is configured but an AuthLDAPURL

isn't -- IOW, avoid silently skipping a misconfigured [or buggy?] LDAP provider.



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1551611 13f79535-47bb-0310-9956-ffa450edef68