Backport review comments from yuzu-emu/yuzu#4382: "yuzu: Add motion and touch configuration from Citra" (#5543)

src/input_common/touch_from_button.h

@@ -16,7 +16,6 @@ class TouchFromButtonFactory final : public Input::Factory<Input::TouchDevice> {
 public:
     /**
      * Creates a touch device from a list of button devices
-     * @param unused
      */
     std::unique_ptr<Input::TouchDevice> Create(const Common::ParamPackage& params) override;
 };