Removing feedback from a control

Use the funtion MTouchFeedback::RemoveFeedbackForControl to remove feedback from a control.

When the control given as parameter to the MTouchFeedback::SetFeedbackArea function is destroyed, then the RemoveFeedbackForControl function must be called, giving the same control as parameter again. This is necessary for removing all the feedback areas, and also for resetting the state information stored by the API implementation.