An Italianni's restaurant in Manila operated by the Bistro Group, a company controlled by private equity fund Navegar MANILA -- Private equity funds have traditionally shown little interest in the Philippines. But the country's recent strong economic performance and favorable demographic trends are putting it on their radar.      In November, Hong Kong-based ADM Capital and an affiliate of Baring Private Equity Asia announced they would lead a $150 million financing package for the construction of five high-end office buildings next to Clark International Airport, northwest of Manila. The deal ranks as one of the largest bets on Philippine...