VOL-3506 Handle ofp_error_msg in ofagent

Change-Id: Ib5d420d6cfbffc2acd0d98010818ae5ff675bb44
diff --git a/internal/pkg/openflow/client.go b/internal/pkg/openflow/client.go
index 91a7096..36ca82b 100644
--- a/internal/pkg/openflow/client.go
+++ b/internal/pkg/openflow/client.go
@@ -261,6 +261,9 @@
 	case *ofp.PacketIn:
 		msgType = "PacketIn"
 		toEqual = false
+	case *ofp.ErrorMsg:
+		msgType = "Error"
+		toEqual = false
 	default:
 		toEqual = true
 	}