Author: Helen Foster
MDL-48748 lang: Fix the regression from the last en_fix merge
See https://moodle.org/mod/forum/discuss.php?d=277584#p1192876
http://git.moodle.org/gw?p=moodle.git;a=commit;h=03ccfe6a877707c3a648e2036044d6eb5b6baf05
http://github.com/moodle/moodle/commit/03ccfe6a877707c3a648e2036044d6eb5b6baf05
+ 2.6 en [auth_ldap_preventpassindb_key,auth_ldap]