retry updating the lastChange attribute with the normal nslcd LDAP connection if the update with the user's connection failed (2f6f6a2 from 0.9)

git-svn-id: http://arthurdejong.org/svn/nss-pam-ldapd/nss-pam-ldapd-0.8@1938 ef36b2f9-881f-0410-afb5-c4e39611909c