HONG KONG (AFX-ASIA) – South China Brokerage has upgraded its rating on Beijing Datang Power Generation Co Ltd (991.HK) to a ‘buy’ from ‘hold’, with a target price of HK$3.10 a share in a 12-month period. (US$1=HK$7.78). The brokerage said in a note to investors that Datang’s current price fails to reflect the company’ forthcoming…