totempg.c: don't truncate group list

* exec/totempg.c (totempg_groups_join): Fix typo s/=/+/ that
would mistakenly truncate totempg group list.

git-svn-id: http://svn.fedorahosted.org/svn/corosync/trunk@2204 fd59a12c-fef9-0310-b244-a6a79926bd2f

exec/totempg.c

@@ -1035,7 +1035,7 @@ int totempg_groups_join (
 	memcpy (&new_groups[instance->groups_cnt],
 		groups, group_cnt * sizeof (struct totempg_group));
 	instance->groups = new_groups;
-	instance->groups_cnt = instance->groups_cnt = group_cnt;
+	instance->groups_cnt += group_cnt;
 
 	hdb_handle_put (&totempg_groups_instance_database, handle);