WASHINGTON (Reuters) - The head of a private investment firm came one step closer to leading the Federal Reserve’s regulatory efforts Wednesday, a key post as President Donald Trump endeavors to trim regulations to boost economic growth. The U.S. Senate voted 62-33 to limit debate on Randal Quarles’ nomination to join the Fed’s Board of Governors, guaranteeing opponents could not delay his confirmation. Quarles is eventually expected to fill the role of vice chair for supervision at the Fed, making him the top official at the central bank in charge of regulatory issues.     The Senate will vote to name Quarles formally to that post at a later date, after he has joined the Fed board. Quarles is a prominent investor and former Treasury Department official. Trump nominated him in July.     Analysts said the appointment of Quarles and the October departure of Federal Reserve Vice Chair Stanley Fischer, who had spoken out against weakening Wall Street regulations, could accelerate Trump’s deregulation agenda, potentially saving banks such as Goldman Sachs Group Inc (GS.N), JPMorgan Chase & Co (JPM.N) and Morgan Stanley (MS.N) billions of dollars. 