German football great Thomas Müller feels a little bit like an Olympic champion because he is the co-owner of Checker, the horse that helped Christian Kukuk win show jumping gold at the Paris Games. “I have to say: hats off, Checker, hats off, Christian Kukuk,” Müller said in an Instagram video on Tuesday, sitting at the table with a gold medal around his neck. “This is my gold medal and you’ve won gold, dear Christian,” said Müller, who named the success “breathtaking” and said he was “absolutely thrilled.” Bayern Munich icon and 2014 World Cup winner Müller said he watched the final in Versa…