By Davide Barbuscia and Dhara Ranasinghe NEW YORK/LONDON (Reuters) – Global investors are preparing for more market mayhem after a monumental week that whipsawed asset prices around the world, as central banks and governments ramped up their fight against inflation. Signs of extraordinary times were everywhere. The Federal Reserve delivered its third straight seventy-five basis point rate hike while Japan intervened to shore up the yen for the first time since 1998. The British pound slid to a fresh 37-year trough against the dollar after the country’s new finance minister unleashed historic t…