[Bug report] use-after-free of lwm2m_close()

### 该问题是怎么引起的？

The function **lwm2m_close()** will destroy all the information about lwm2m link. It calls the function **prv_deleteServerList()** to free the linked list **contextP->serverList** and the function **prv_deleteTransactionList()** to clear the linked list **contextP->transactionList** as shown in https://gitee.com/LiteOS/LiteOS/blob/master/components/connectivity/lwm2m/core/liblwm2m.c?_from=gitee_search#L226. When the callback function **prv_handleRegistrationReply()** is called by the **function prv_deleteTransactionList()**, it tries to access the memory pointed by the pointer **transacP->userData** as shown in https://gitee.com/LiteOS/LiteOS/blob/master/components/connectivity/lwm2m/core/registration.c?_from=gitee_search#L225. However, the pointer **transacP->userData** points to the memory server aligned by the function **prv_register()** as shown in https://gitee.com/LiteOS/LiteOS/blob/master/components/connectivity/lwm2m/core/registration.c?_from=gitee_search#L318 and already freed by the function **prv_deleteServerList()** before the function **prv_deleteTransactionList()**. This will lead to a use-after-free fault.

### 重现步骤

Run the lwm2m demo project under client mode and use the bytes below as the input packet.

0x60, 0x45, 0x00, 0x07, 0xc0, 0xff, 0x77, 0x80, 0x72, 0x6c, 0x64

### 报错信息

Due to the fact that lacking efficient error checking mechanism, the developer or tester needs to check this fault by debugging.