[China Mobile to buy back $12.6 billion of its HK shares] China Mobile Ltd will buy back up to $12.6 billion worth of its Hong Kong listed shares on the market, as the company prepares for its 48.7 billion yuan ($7.7 billion) listing in Shanghai on Wednesday, China’s biggest public share offering in a decade. The company told the Hong Kong Stock Exchange it would press ahead with a plan to buy back up to 2.05 billion shares using existing cash and working capital. China Mobile’s (0941.HK) Hong Kong shares rose 1.91 percent on Tuesday to close at HK$48 ($6.16),...