MQTT originator and receiver can be optional

Signed-off-by: reinaortega <miguelangel.reinaortega@etsi.org>

LibOneM2M/OneM2M_Types.ttcn

@@ -8908,8 +8908,8 @@ type record CoapBindingDesc {
 type record MqttBindingDesc {
 	ProtocolBindings bindingProtocol (e_mqtt),
 	BindingDesc      bindingDesc,
-	XSD.ID       	 originator,
-	XSD.ID		     receiver
+	XSD.ID       	 originator optional,
+	XSD.ID		     receiver optional
 	// TODO To be completed
 }