Merge branch 'bugfix/cpp_compilation' into 'master'

Fix: Compilation in C++ with multiple subscribe

See merge request espressif/esp-mqtt!171

(cherry picked from commit 88413ec3f27102daa805ae1992dd145b42d4690d)

47da99fb Fix: Compilation in C++ with multiple subscribe

Author: euripedesrocha

include/mqtt_client.h

@@ -426,6 +426,11 @@ esp_err_t esp_mqtt_client_disconnect(esp_mqtt_client_handle_t client);
 esp_err_t esp_mqtt_client_stop(esp_mqtt_client_handle_t client);
 
 
+#ifdef __cplusplus
+
+#define esp_mqtt_client_subscribe esp_mqtt_client_subscribe_single
+
+#else
 /**
  * @brief Convenience macro to select subscribe function to use.
  *
@@ -445,6 +450,7 @@ esp_err_t esp_mqtt_client_stop(esp_mqtt_client_handle_t client);
       esp_mqtt_topic_t*: esp_mqtt_client_subscribe_multiple \
     )(client_handle, topic_type, qos_or_size)
 
+#endif /* __cplusplus*/
 /**
  * @brief Subscribe the client to defined topic with defined qos
  *