By Luc Cohen NEW YORK (Reuters) -A former Goldman Sachs banker should be convicted of helping loot billions of dollars from Malaysia’s 1MDB sovereign wealth fund and causing “immeasurable” harm, a U.S. prosecutor told jurors in her closing argument on Monday. Roger Ng, Goldman’s former top investment banker for Malaysia, faces charges he helped his former boss Tim Leissner embezzle hundreds of millions of dollars from the fund, launder the proceeds and bribe officials to win business for Goldman. Assistant U.S. Attorney Alixandra Smith said Ng received more than $35 million in kickbacks from t…