move todo item outside doxygen comment

Author: soheilshahrouz

libs/libarchfpga/src/device_grid.h

@@ -19,11 +19,11 @@ struct t_grid_tile {
     const t_metadata_dict* meta = nullptr;
 };
 
+
+//TODO: All of the functions that use helper functions of this class should pass the layer_num to the functions, and the default value of layer_num should be deleted eventually.
 /**
  * @class DeviceGrid
  * @brief Represents the FPGA fabric. It is used to get information about different layers and tiles.
- *
- * TODO: All of the functions that use helper functions of this class should pass the layer_num to the functions, and the default value of layer_num should be deleted eventually.
  */
 class DeviceGrid {
   public: