Why Singer may have taken a position in Arm Holdings.Billionaire Paul Singer and his fund, Elliott Investment Management, is making waves. The fund had been in active discussions with Starbucks on a turnaround plan that subsequently saw the company name a new CEO. It's also been in a very public fight with Southwest Airlines and just nominated 10 new board members for the airline.In tech land, meanwhile, the fund dumped its shares of Nvidia (NVDA 4.35%) while starting a new position in Arm Holdings (ARM 1.5 ...