Delay makes Chrysler stake buy costlier -Fiat CEO

* U.S. govt wants to sell stake "as soon as practical" * Fiat shares up 3 pct, outperforming auto sector * Fiat to consolidate Chrysler from June 1 (Adds details, background, shares) TURIN, Italy, May 25 (Reuters) - Italian carmaker Fiat's (FIA...