parametrized disable_flow_collection for disable flow collection at vrouter 2.2X
diff --git a/opencontrail/files/2.2/contrail-vrouter-agent.conf b/opencontrail/files/2.2/contrail-vrouter-agent.conf
index 4ff305a..3b6e9af 100644
--- a/opencontrail/files/2.2/contrail-vrouter-agent.conf
+++ b/opencontrail/files/2.2/contrail-vrouter-agent.conf
@@ -51,6 +51,7 @@
 
 # Disable sending of flow samples to collector. Possible values are 0 and 1
 # disable_flow_collection=false
+disable_flow_collection={{ compute.get('disable_flow_collection', 'false') }}
 
 # Encapsulation type for tunnel. Possible values are MPLSoGRE, MPLSoUDP, VXLAN
 # tunnel_type=