typo

Change-Id: I8e4048015dec6e0dabea0d5c6b6377ffc2151068
diff --git a/fluentd/label/default_output/elasticsearch.yml b/fluentd/label/default_output/elasticsearch.yml
index 5960c49..aa96b31 100644
--- a/fluentd/label/default_output/elasticsearch.yml
+++ b/fluentd/label/default_output/elasticsearch.yml
@@ -1,7 +1,7 @@
 classes:
 - service.fluentd.agent.output.elasticsearch
 parameters:
-  _params:
+  _param:
     fluentd_elasticsearch_host: 127.0.0.1
     elasticsearch_port: 9200
   fluentd: