genmatch.c (expr::gen_transform): Shortcut re-simplifying of converts to avoid uninteresting noise from the...

2015-07-01  Richard Biener <rguenther@suse.de>

	* genmatch.c (expr::gen_transform): Shortcut re-simplifying
	of converts to avoid uninteresting noise from the conversion
	simplifying patterns.

From-SVN: r225223