Update LoRaMac-node to Version 4.4.4，fix Security breach found by Tencent Blade Team please refer to security advisory - CVE-2020-11068

fix Security breach found by Tencent Blade Team please refer to security advisory - CVE-2020-11068

components/connectivity/LoraWAN/mac/LoRaMacSerializer.h

@@ -36,6 +36,11 @@
  */
 #ifndef __LORAMAC_SERIALIZER_H__
 #define __LORAMAC_SERIALIZER_H__
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
 #include <stdint.h>
 #include "LoRaMacMessageTypes.h"
 
@@ -97,5 +102,9 @@ LoRaMacSerializerStatus_t LoRaMacSerializerData( LoRaMacMessageData_t* macMsg );
 
 /*! \} addtogroup LORAMAC */
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif // __LORAMAC_SERIALIZER_H__