copyright (cherry picked from commit e3d74bdd7faca1583cc4dbea56bbe04a44db9e47)
[master] fix null deref in some DLZ modules 3691. [contrib] Address null pointer dereference in LDAP and MySQL DLZ modules.
[master] make LDAP DLZ module work with older DLZ
[master] DLZ modules: filesystem, ldap, wildcard 3523. [contrib] Ported filesystem and ldap DLZ drivers to dynamically-loadable modules, and added the "wildcard" module based on a contribution from Vadim Goncharov <vgoncharov@nic.ru>. [RT #23569]