By Aida Pelaez-Fernandez MEXICO CITY (Reuters) - Latin America is increasingly seen as an attractive market for mergers and acquisitions (M&A), with the ongoing U.S.-China trade spat helping to whet investor appetite for opportunities in the region, a KPMG survey of executives showed on Monday. The survey of nearly 400 executives across 14 countries globally showed technology, financial services and energy sectors leading the way and Mexico overtaking regional heavyweight Brazil for the top spot in M&A activity. "Opportunities already outweigh challenges," said Gerardo Rojas, head of KPMG's Advisory Practice in Mexico and Central America. "The risks investors see in...