Malaysia’s king on Saturday appointed Malay nationalist leader Muhyiddin Yassin as the country’s new prime minister, dramatically upending expectations that the 94-year-old elder statesman Mahathir Mohamad would keep his job after cobbling together support at the eleventh hour following a fraught five days of leaderless turmoil and frantic horse-trading in the country.In a statement, the palace said Sultan Abdullah Sultan Ahmad Shah had conducted interviews with all MPs last week and found that…