UK alcoholic drinks giant Diageo reported that its Burger King fastfood subsidiary is returning its best US sales growth in years. The news gives a shot in the arm to a turnaround that is attracting a number of suitors for BK. Known bidders include private investment funds Texas Pacific Group and Thomas H. Lee Partners, and trade buyer Triarc Cos, which owns the Arby's restaurant chain. Other bidders remain in the frame too, sources close to the company say.