fix: 出厂默认 topic 使用真实设备序列号 + PRINT 修正

- cfig_flash.c: factory_dev_info() 用 gMacAddr 生成真实主题 dld960/{SN}/srv + dld960/{SN}/dev
- net_srv.h: TOPIC_DEFAULT 加注释标明为格式模板
- net_srv.c: 修复上次提交的 PRINT 宏转义异常

vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/net_srv.c

@@ -141,9 +141,7 @@ void dg_subscribe_display_topic(void)
     strcpy(mBuff, (char *)g_iot_topic.topic_sub);
     
     {
-    PRINT("
-\nWill subscribe display_topic:\n%s
-\n", mBuff);
+    PRINT("\nWill subscribe display_topic:\n%s\n", mBuff);
     }
     MQTT_Subscribe(mBuff, 1);
     
@@ -219,11 +217,6 @@ void dev_response_heartbeat(char *dat)
 
 void mqtt_deserialize_publish(char* topic, char* msg, int length)
 {    
-//    if(g_flag_debug)
-//    {
-//        printf("display_mqtt_callback rev topic: %s\n msg:%s, len:%d
-\n", topic, msg, length);
-//    }
     // V1.01: 使用配置的 topic_sub 匹配，而非硬编码默认值
     if(strstr(topic, (char *)g_iot_topic.topic_sub) != NULL)
     {