Support connecting to multiple OpenFlow controllers

Change-Id: I0989d5031fb2d4f5aa78ba0e4576e465f826a419
diff --git a/internal/pkg/openflow/echo.go b/internal/pkg/openflow/echo.go
index af850a4..7358a0f 100644
--- a/internal/pkg/openflow/echo.go
+++ b/internal/pkg/openflow/echo.go
@@ -22,7 +22,7 @@
 	"github.com/opencord/voltha-lib-go/v3/pkg/log"
 )
 
-func (ofc *OFClient) handleEchoRequest(request *ofp.EchoRequest) {
+func (ofc *OFConnection) handleEchoRequest(request *ofp.EchoRequest) {
 	if logger.V(log.DebugLevel) {
 		js, _ := json.Marshal(request)
 		logger.Debugw("handleEchoRequest called",