[VOL-2440] : code changes to facilitate portstateupdate towards core

Change-Id: I9ef97346c064f59ca79add5472683c796f1b116b
diff --git a/pkg/adapters/adapterif/core_proxy_if.go b/pkg/adapters/adapterif/core_proxy_if.go
index 9286c0d..c7af374 100644
--- a/pkg/adapters/adapterif/core_proxy_if.go
+++ b/pkg/adapters/adapterif/core_proxy_if.go
@@ -48,4 +48,6 @@
 	GetChildDevices(ctx context.Context, parentDeviceID string) (*voltha.Devices, error)
 	SendPacketIn(ctx context.Context, deviceID string, port uint32, pktPayload []byte) error
 	DeviceReasonUpdate(ctx context.Context, deviceID string, deviceReason string) error
+	PortStateUpdate(ctx context.Context, deviceID string, pType voltha.Port_PortType, portNo uint32,
+		operStatus voltha.OperStatus_OperStatus) error
 }