At 2:30 a.m. one day in mid-November, after the election of Donald J. Trump to the presidency of the United States, the telephone rang in the official residence of Prime Minister Najib Razak of Malaysia. Najib’s wife Rosmah Mansor answered the telephone. On the other end was businessman Syed Azman of Weststar Group, a sprawling Malaysia-based conglomerate with interests in cars, aviation, construction, defense and engineering. Azman’s 40 helicopters shuttle people and goods to offshore oil platforms.