IMP-1332: Remove unused 'nss-pam-ldapd' openldap contrib module from /thirdparty

Change-Id: I478d9238864052981377a03cd90d37f60129c70e
Reviewed-on: http://gerrit.ent.cloudera.com:8080/2081
Reviewed-by: Ishaan Joshi <ishaan@cloudera.com>
Tested-by: jenkins