EMERGING MARKETS-Latam stocks flat after China data

* China reports stronger than expected Dec trade data * Retailer Cia Hering plunges after sales miss expectations * Brazil Bovespa up 0.16 pct, Mexico IPC steady By Asher Levine and Danielle Assalve SAO PAULO/MEXICO CITY, Jan 10 (Reuters) - Latin American stocks edged up on Thursday after stronger-than-expected Chinese economic data boded well for Brazil's commodity-rich stock market but failed to spur much buying after a recent rally. Brazil's benchmark Bovespa stock index