Arista Rest Driver PortStatistics Implement

Change-Id: Ifaf6286b0d54b453d2a4471e1a117a90775bc43a
diff --git a/drivers/arista/src/main/resources/arista-drivers.xml b/drivers/arista/src/main/resources/arista-drivers.xml
index 2f29988..18d0001 100644
--- a/drivers/arista/src/main/resources/arista-drivers.xml
+++ b/drivers/arista/src/main/resources/arista-drivers.xml
@@ -24,6 +24,8 @@
                    impl="org.onosproject.drivers.arista.BridgeConfigAristaImpl"/>
         <behaviour api="org.onosproject.net.behaviour.LinkDiscovery"
                    impl="org.onosproject.drivers.arista.LinkDiscoveryAristaImpl"/>
+        <behaviour api="org.onosproject.net.device.PortStatisticsDiscovery"
+                   impl="org.onosproject.drivers.arista.PortStatisticsImpl"/>
     </driver>
 </drivers>