configuration/input: Add support for mouse button clicks

Supports the Left, Right, Middle, Backward and Forward mouse buttons.

src/yuzu/configuration/configure_mouse_advanced.h

@@ -49,6 +49,9 @@ private:
     /// Finish polling and configure input using the input_setter
     void SetPollingResult(const Common::ParamPackage& params, bool abort);
 
+    /// Handle mouse button press events.
+    void mousePressEvent(QMouseEvent* event) override;
+
     /// Handle key press events.
     void keyPressEvent(QKeyEvent* event) override;
 
@@ -67,5 +70,5 @@ private:
 
     /// A flag to indicate if keyboard keys are okay when configuring an input. If this is false,
     /// keyboard events are ignored.
-    bool want_keyboard_keys = false;
+    bool want_keyboard_mouse = false;
 };