Trac Ticket #437 - variable dn should not be used in ldbm_back_delete
https://fedorahosted.org/389/ticket/437
Fix description: When SLAPI_DELETE_TARGET_DN was replaced with
SLAPI_DELETE_TARGET_SDN, removing obsolete variable dn was
incomplete. Actually, the variable dn is still referred in
some error messages. This patch sets the value from Slapi_DN
to the dn variable.
(cherry picked from commit b37e0c2e878ecef8c46449ce4e44a3c0deb344f2)