EMERGING MARKETS-Brazil stocks up as index futures expire, Fed eyed

* Brazil Bovespa up 1.05 pct, Mexico IPC little changed SAO PAULO, Dec 18 (Reuters) - Brazilian stocks rose on Wednesday as investors picked up shares of steelmakers and homebuilders, with Bovespa index futures set to expire at the close of the session. The expirations often create volatility as investors try to push the index above or below strike prices. Mexico's IPC index remained little changed, while Chile's bourse edged lower. Brazil's benchmark Bovespa stock index rose fo