By Jennifer Newton A smiling Prince Harry was spotted preparing to leave the UK after dashing to London to visit King Charles following his shock cancer diagnosis. The Duke of Sussex appeared happy and relaxed as he arrived at Heathrow’s Windsor Suite ahead of his flight back to Los Angeles following his whirlwind trip to the UK. Dressed down in jeans, a light coloured top and a black jacket, Harry was greeted by a doorman in a top hat before entering the exclusive suit. He walked with his hands in his pockets. It came just 24 hours after he initially landed in his homeland from California – a…