GLOBAL MARKETS-Stocks cut gains as U.S. legislators support Syria action

* U.S. stocks trim early gains; Microsoft slumps after Nokia deal * Treasury bond selling resumes * U.S. manufacturing sector expands * U.S. dollar hits six-week high By Caroline Valetkevitch NEW YORK, Sept 3 (Reuters) - World stock markets were up slightly on Tuesday but cut gains after U.S. congressional leaders voiced support for military intervention in Syria, while bond yields rose and the dollar gained on strong U.S. data. Wall Street stocks rallied at the openin