ANDREW MACASKILL and MUVIJA M BORIS Johnson returned to Britain as he considers an audacious attempt to win a second term as prime minister only weeks after he was forced to step down, with some colleagues warning his comeback could create more political chaos. Potential candidates to replace Prime Minister Liz Truss, who quit on Thursday after six weeks in office, were embarking on a frantic weekend of lobbying to secure enough nominations to enter the leadership contest before Monday's deadline. Johnson, who was on holiday in the Caribbean when Truss resigned, has not commented publicly about a bid for his old…