Add config factory reset

Signed-off-by: YoungSoo Shin <shinys000114@gmail.com>

main/include/nconfig.h

@@ -45,6 +45,11 @@ enum nconfig_type
     NCONFIG_TYPE_MAX,   ///< Sentinel for the maximum number of configuration types.
 };
 
+/**
+ * @brief Erase all of nvs data and restart system
+ */
+void reset_nconfig();
+
 /**
  * @brief Checks if a specific configuration value has been set.
  *