* Fund's target raised from $5 bln after strong investor interest. : HONG KONG (Reuters) - Carlyle Group (CG.O) is set to close its biggest-ever Asia private equity fund at $6.5 billion, people with direct knowledge of matter said, in a deal that adds to the record levels of funds seeking deals in the region. The private equity giant had initially targeted a fund of $5 billion but raised its expectations following a strong response from its investors, known as limited partners, said the people.