add interface of MessageParcelAppend

Signed-off-by: Nliubb_0516 <liubeibei8@huawei.com>

interfaces/innerkits/ipc_core/include/message_parcel.h

@@ -50,6 +50,7 @@ public:
     {
         needCloseFd_ = true;
     };
+    bool MessageParcelAppend(MessageParcel &data);
 
 private:
 #ifndef CONFIG_IPC_SINGLE