ControllerInterface: Make UpdateInput / UpdateOutput return void

The return values here have never been checked, so it doesn't make sense
to return a value to begin with.

Source/Core/InputCommon/ControllerInterface/Device.h

@@ -100,8 +100,8 @@ public:
 	virtual std::string GetName() const = 0;
 	virtual int GetId() const = 0;
 	virtual std::string GetSource() const = 0;
-	virtual bool UpdateInput() { return true; }
-	virtual bool UpdateOutput() { return true; }
+	virtual void UpdateInput() {}
+	virtual void UpdateOutput() {}
 
 	const std::vector<Input*>& Inputs() const { return m_inputs; }
 	const std::vector<Output*>& Outputs() const { return m_outputs; }