By Sruthi Shankar (Reuters) -European stocks rallied on Wednesday, with banks leading the gains, after the European Central Bank said its rate-setting Governing Council would hold an unscheduled meeting to discuss the recent sell-off in government bond markets. An index of euro zone shares climbed 1.5%, while the pan-European STOXX 600 added 1%. Italian bank stocks, which have taken a hit recently on fears about Rome’s surging debt costs, rallied, as the government bond yields tumbled. Shares of Unicredit, Intesa Sanpaolo and BPER Banca rose between 4.3% and 5.6%, while the broader Italian ban…