优化通道同步添加对SN的判断，精简代码

648540858

2022-04-17 0dc1807f621ce9077b58dff40ad4485c9a3d6c40

 src/main/java/com/genersoft/iot/vmp/gb28181/session/SsrcConfig.java

@@ -81,7 +81,6 @@
            isUsed.remove(sn);
            notUsed.add(sn);
        }catch (NullPointerException e){
            System.out.printf("11111");
        }
    }