Merger. Mania. Again. Another potential blockbuster deal in the ever-evolving semiconductor sector helped light a fire among technology stocks Wednesday as the rest of the stock market followed higher. The Nasdaq composite led with a 1.5% rebound, more than recouping Tuesday’s 1.1% decline. Volume increased nearly 5%, a positive sign for the bulls; it indicated that institutional trading desks had gotten busier and demanded more stocks.