InputCommon: Use value of "Modifier" button "Range" setting rather than always applying 50%.

Make "Clear" button reset "Modifier" "Range" settings to 50%.

Source/Core/InputCommon/ControllerEmu/ControlGroup/Tilt.h

@@ -31,6 +31,8 @@ public:
   ControlState GetMaxRotationalVelocity() const;
 
 private:
+  Control* GetModifierInput() const override;
+
   SettingValue<double> m_max_angle_setting;
   SettingValue<double> m_max_rotational_velocity;
 };