(Reuters) - UK shares rebounded for a second straight day after a steep sell-off earlier this week on rising fears over the impact from the coronavirus, though the bounce lost some punch as oil majors dipped alongside crude prices on U.S. stockpile data.The FTSE 100 index , which had risen as much as 0.5% earlier, ended only marginally higher. Shell and BP lagged after inventory and stockpiling data from the U.S. Energy Information Administration.The FTSE 250 , which had slumped more than 2%..