LONDON (Reuters) – Major central banks have stepped up their fight against runaway inflation, unleashing another 350 basis points of hikes in a pivotal week in which policymakers are determined to show they mean business. The Federal Reserve raised U.S. rates by three-quarters of a percentage point for a third straight time on Wednesday, while the British, Swiss and Norwegian central banks all delivered large hikes on Thursday. Central banks in the 10 big developed economies have raised rates by a combined 1,965 basis points in this cycle to date, with Japan the holdout “dove”, sticking on Thu…