UPDATE 1-Speculators push U.S. dollar bets to six-week high-CFTC, Reuters

(Adds details on dollar, yen, Mexican peso contracts, analyst comments, table, byline) By Gertrude Chavez-Dreyfuss NEW YORK, Sept 30 (Reuters) - Speculators boosted net longs on the U.S. dollar to their highest in six weeks, Reuters calculations and data from the Commodity Futures Trading Commission showed on Friday, in a volatile week that saw the greenback rack up gains as a safe haven due to the troubles at Deutsche Bank. The value of the dollar's net long position rose to $9.7