By Martyn Herman LONDON (Reuters) – An own goal by Jakub Kiwior and a thumping late strike by Luis Diaz sealed a 2-0 victory for Liverpool at Arsenal in the weekend’s headline FA Cup third round tie as the hosts’ dismal form extended into the New Year on Sunday. Arsenal wasted a sackful of chances in the first half and were made to pay as Liverpool skipper Trent Alexander-Arnold’s free kick glanced off the head of Kiwior in the 80th minute. Diaz then made sure of eight-time winners Liverpool’s place in the fourth round draw as he lashed home in stoppage time. Premier League leaders Liverpool h…