BugFix: lower_Start Added special case support for Shr, Shrs, Shl
BugFix: lower_Start
Added special case support for Shr, Shrs, Shl

[r7789]

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