Allow the Bad node to be set in set_store(). This is neccessary, because Bad might happen as a result of optimization.
Allow the Bad node to be set in set_store(). This is neccessary, because Bad might happen as a result of optimization.

[r8410]

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