removed definition of old type_visited flag restored type_visited() function declaration
removed definition of old type_visited flag
restored type_visited() function declaration

[r6456]

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