Disable collectd syslog logging

https://github.com/Mirantis/mk-lab-salt-model/pull/176
diff --git a/collectd/client/output/heka.yml b/collectd/client/output/heka.yml
index 5efb3ac..9550961 100644
--- a/collectd/client/output/heka.yml
+++ b/collectd/client/output/heka.yml
@@ -14,3 +14,4 @@
           port: ${_param:collectd_metric_collector_port}
       read_interval: 10
       use_fqdn: false
+      syslog_logging: false