EMERGING MARKETS-Latam stocks continue decline to long unseen lows

* Banorte announces global share offering, stock plummets * Mexico IPC down 1.03 pct, Brazil Bovespa 1.18 pct off By Asher Levine and Danielle Assalve SAO PAULO, June 12 (Reuters) - Mexican stocks fell to their lowest in nearly a year on Wednesday, driven by a sharp fall in the shares of Grupo Financiero Banorte, while Brazilian stocks closed at their worst level in nearly two years. Banorte, Mexico's fourth-largest lender by assets, said the up to $3 billion offer would includ