Vendor import the latest GPLv2 libstdc++ sources.
    
    It happens to be that while libstdc++ is a subset of gcc which was
    changed to GPLv3, libstdc++ was kept under LGPLv2 until the end of
    the 4.2 branch (gcc 4.2.4) (@ GRN 135556).
    
    Obtained from:	svn://gcc.gnu.org/svn/gcc/branches/gcc-4_2-branch/libstdc++-v3
    Requested by:	pfg
    Reviewed by:	pfg