mod_ldap: prevent the possiblity of an infinite loop in the LDAP

statistics display.
PR:	29216
Obtained from:
Submitted by:
Reviewed by:	minfrin, bnicholes, jim


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/APACHE_2_0_BRANCH@105428 13f79535-47bb-0310-9956-ffa450edef68