Reckitt Benckiser has retained Merrill Lynch as the company considers the possible acquisition of Pfizer’s consumer product group, according to a report in the Sunday Times of London. Pfizer, the world’s largest drug maker, said last month it may spin off or sell Pfizer Consumer Healthcare, which includes brands such as Listerine mouthwash. Reckitt bought Boots Group Plc’s  over-the-counter drugs business for 1.93 billion pounds last year....