添加缺少的导入

src/main/java/com/genersoft/iot/vmp/gb28181/transmit/cmd/impl/SIPCommanderFroPlatform.java

@@ -2,6 +2,7 @@ package com.genersoft.iot.vmp.gb28181.transmit.cmd.impl;
 
 import com.alibaba.fastjson2.JSON;
 import com.alibaba.fastjson2.JSONObject;
+import com.genersoft.iot.vmp.gb28181.SipLayer;
 import com.genersoft.iot.vmp.gb28181.bean.*;
 import com.genersoft.iot.vmp.gb28181.event.SipSubscribe;
 import com.genersoft.iot.vmp.gb28181.transmit.SIPSender;