(Corrects to say “HSBC Holdings” not “HSBA” in second paragraph) * FTSE 100, FTSE 250 add 0.5% each Oct 5 (Reuters) - London’s FTSE 100 rose on Tuesday, led by heavyweight banks as they tracked higher yields, while fast-food chain Greggs jumped after raising its profit forecast on strong sales. The blue-chip FTSE 100 index gained 0.5% by 0705 GMT after three straight sessions of falls, with HSBC Holdings , Royal Dutch Shell, Flutter Entertainment and Lloyds Group being among the top boosts. The domestically focussed mid-cap index advanced 0.5%. Baker and fast-food chain Greggs was the top boost with a gain of 3.7% after it raised its full-year profit outlook despite supply chain and staffing disruptions. Inspiration Healthcare Group added 4.1% after reporting a 133% rise in first-half profit. Britain’s auto sector dropped 0.8% after preliminary industry data showed new car registrations marked the weakest September for at least 23 years. Melrose Industries declined 1.5% after saying the global chip shortage led to a surge in monthly cancellations from its customers in the auto industry.