ISTANBUL - Garanti Bank, Turkey's third-biggest lender, said on Tuesday a small number of its customers had cancelled credit cards and withdrawn savings in protest at a sister media company's coverage of anti-government demonstrations.Tens of thousands of people have staged protests in cities across Turkey and many have complained that domestic broadcasters and newspapers are not adequately covering their action out of fear of government reprisals.Dogus Holding, which owns a major stake in Garanti, also controls the NTV television station, which has angered the protesters with its coverage.