bugfix: float cmp pnc have always ia32_pn_Cmp_Unsigned set
bugfix: float cmp pnc have always ia32_pn_Cmp_Unsigned set

[r15690]

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