Updated mysqld--help test and result (MDEV-6717, MDEV-6659).

mysql-test/r/mysqld--help.result

@@ -1198,7 +1198,6 @@ wsrep-certify-nonPK TRUE
 wsrep-cluster-address 
 wsrep-cluster-name my_wsrep_cluster
 wsrep-convert-LOCK-to-trx FALSE
-wsrep-data-home-dir 
 wsrep-dbug-option 
 wsrep-debug FALSE
 wsrep-desync FALSE
@@ -1212,7 +1211,7 @@ wsrep-mysql-replication-bundle 0
 wsrep-node-address 
 wsrep-node-incoming-address AUTO
 wsrep-notify-cmd 
-wsrep-on FALSE
+wsrep-on TRUE
 wsrep-provider none
 wsrep-provider-options 
 wsrep-recover FALSE

mysql-test/t/mysqld--help.test

@@ -20,7 +20,8 @@ perl;
   # their paths may vary:
   @skipvars=qw/basedir open-files-limit general-log-file log plugin-dir
                log-slow-queries pid-file slow-query-log-file log-basename
-               datadir slave-load-tmpdir tmpdir socket wsrep-node-name/;
+               datadir slave-load-tmpdir tmpdir socket wsrep-node-name
+               wsrep-data-home-dir/;
 
   # Plugins which may or may not be there:
   @plugins=qw/innodb ndb archive blackhole federated partition ndbcluster