Use irg-property framework in a proper way.
Use irg-property framework in a proper way.

Especially, do not confirm consistent out edges.
This fixes ack/t7.c on SPARC.

davidgiven/libfirm,8l/libfirm,8l/libfirm,libfirm/libfirm,davidgiven/libfirm,killbug2004/libfirm,8l/libfirm,jonashaag/libfirm,davidgiven/libfirm,jonashaag/libfirm,killbug2004/libfirm,jonashaag/libfirm,MatzeB/libfirm,davidgiven/libfirm,8l/libfirm,jonashaag/libfirm,killbug2004/libfirm,MatzeB/libfirm,davidgiven/libfirm,MatzeB/libfirm,jonashaag/libfirm,davidgiven/libfirm,killbug2004/libfirm,libfirm/libfirm,libfirm/libfirm,MatzeB/libfirm,jonashaag/libfirm,jonashaag/libfirm,killbug2004/libfirm,killbug2004/libfirm,MatzeB/libfirm,killbug2004/libfirm,libfirm/libfirm,8l/libfirm,davidgiven/libfirm,8l/libfirm,8l/libfirm,MatzeB/libfirm,MatzeB/libfirm,libfirm/libfirm