fix mem leak in recv message error, always free msg

@@ -454,7 +454,6 @@ int SrsRtmpClient::connect_app(string app, string tc_url)
     if (true) {
         SrsConnectAppPacket* pkt = new SrsConnectAppPacket();
         
-        pkt->command_object = SrsAmf0Any::object();
         pkt->command_object->set("app", SrsAmf0Any::str(app.c_str()));
         pkt->command_object->set("swfUrl", SrsAmf0Any::str());
         pkt->command_object->set("tcUrl", SrsAmf0Any::str(tc_url.c_str()));

@@ -382,6 +382,7 @@ int SrsProtocol::recv_message(SrsMessage** pmsg)
             if (ret != ERROR_SOCKET_TIMEOUT && !srs_is_client_gracefully_close(ret)) {
                 srs_error("recv interlaced message failed. ret=%d", ret);
             }
+            srs_freep(msg);
             return ret;
         }
         srs_verbose("entire msg received");

@@ -477,6 +477,10 @@ protected:
 public:
     std::string command_name;
     double transaction_id;
+    /**
+    * alloc in packet constructor,
+    * so, directly use it, never alloc again.
+    */
     SrsAmf0Object* command_object;
 public:
     SrsConnectAppPacket();