fix: 场景联动RPC失败问题修复

@@ -249,7 +249,7 @@ class DeviceActorMessageProcessor extends AbstractContextAwareMsgProcessor {
 
         //Thingskit function
         JsonNode old = JacksonUtil.toJsonNode(request.getAdditionalInfo());
-        ObjectNode additional = old.isEmpty() ?mapper.createObjectNode():(ObjectNode)old;
+        ObjectNode additional = (old == null || old.isEmpty()) ?mapper.createObjectNode():(ObjectNode)old;
         if(!additional.has("cmdType")){
             additional.put("cmdType", DeviceTransportType.MQTT.name());
         }