Replace slots with Q_SLOTS

src/equalizer/equalizer.h

@@ -73,7 +73,7 @@ class Equalizer : public QDialog {
  protected:
   void closeEvent(QCloseEvent*) override;
 
- private slots:
+ private Q_SLOTS:
   void StereoBalancerEnabledChangedSlot(const bool enabled);
   void StereoBalanceSliderChanged(const int value);
   void EqualizerEnabledChangedSlot(const bool enabled);

src/equalizer/equalizerslider.h

@@ -43,7 +43,7 @@ class EqualizerSlider : public QWidget {
  Q_SIGNALS:
   void ValueChanged(const int value);
 
- public slots:
+ public Q_SLOTS:
   void OnValueChanged(const int value);
 
  private: