By Andy Bruce and David Milliken LONDON (Reuters) -Bank of England Deputy Governor Jon Cunliffe said on Monday that the central bank may not need to take sustained action to prevent inflation expectations from becoming engrained in public thinking, as there were few signs of this to date. Cunliffe, the only BoE policymaker to vote against the central bank’s March 16 decision to raise Bank Rate to 0.75% from 0.5%, warned against comparisons with 1970s when a self-reinforcing spiral of inflation and expectations took hold. Cunliffe said he recognised the risk of second-round effects, and that fu…