configure_graphics: Make use of qOverload in signals/slots

While we're in the same area, we can make use of qOverload to tidy up
some function pointer casts.

src/yuzu/configuration/configure_graphics.cpp

@@ -28,9 +28,9 @@ ConfigureGraphics::ConfigureGraphics(QWidget* parent)
 
     SetConfiguration();
 
-    connect(ui->api, static_cast<void (QComboBox::*)(int)>(&QComboBox::currentIndexChanged), this,
+    connect(ui->api, qOverload<int>(&QComboBox::currentIndexChanged), this,
             [this] { UpdateDeviceComboBox(); });
-    connect(ui->device, static_cast<void (QComboBox::*)(int)>(&QComboBox::activated), this,
+    connect(ui->device, qOverload<int>(&QComboBox::activated), this,
             [this](int device) { UpdateDeviceSelection(device); });
 
     connect(ui->bg_button, &QPushButton::clicked, this, [this] {