Fix: specify the source MAC as fake GW MAC for self ARP reply case

Change-Id: Ie59ca9143267da6737a3b18fdcfa53c54caea1f9
diff --git a/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/OpenstackSwitchingArpHandler.java b/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/OpenstackSwitchingArpHandler.java
index feb06cc..3b805e8 100644
--- a/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/OpenstackSwitchingArpHandler.java
+++ b/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/impl/OpenstackSwitchingArpHandler.java
@@ -357,6 +357,7 @@
                             .setArpOp(ARP.OP_REPLY)
                             .setArpSha(MacAddress.valueOf(gatewayMac))
                             .setArpSpa(Ip4Address.valueOf(gateway))
+                            .setEthSrc(MacAddress.valueOf(gatewayMac))
                             .setOutput(PortNumber.IN_PORT);
 
                     osFlowRuleService.setRule(