[VOL-3141] Created Span for various Openflow and Ofagent operations

Change-Id: I49e371479edc087dcf89bd60b43c000ab0bb5547
diff --git a/internal/pkg/openflow/echo.go b/internal/pkg/openflow/echo.go
index e02e00f..9d0026f 100644
--- a/internal/pkg/openflow/echo.go
+++ b/internal/pkg/openflow/echo.go
@@ -24,6 +24,9 @@
 )
 
 func (ofc *OFConnection) handleEchoRequest(ctx context.Context, request *ofp.EchoRequest) {
+	span, ctx := log.CreateChildSpan(ctx, "openflow-echo")
+	defer span.Finish()
+
 	if logger.V(log.DebugLevel) {
 		js, _ := json.Marshal(request)
 		logger.Debugw(ctx, "handleEchoRequest called",