Prince William joked about his “Harry Potter scar” as he recalled a childhood accident during today’s outing. The Prince of Wales referred to his head wound as he met with businesses and organisations which promote the benefits of seaweed. During a visit to Cardiff Metropolitan University, he told entrepreneurs how he got the injury after being hit with a golf club as a child. Pointing to a mark above his left eye, William also admitted he has never played the sport since. The prince chatted to Pierre Paslier, co-founder and co-chief executive officer of Notpla, a former category winner in Wil…