packages/gcc/gcc-cross_4.2.2: Attempt to fix the fortran issue

packages/gcc/gcc-cross_4.2.2: Attempt to fix the fortran issue
    f951 was not executable because libmpfr and libgmp which were build by
    OpenEmbedded were not found. They resist in the staging lib directory and
    we do not have the LD_LIBRARY_PATH set.
    --enable-rpath for gcc was not an option, as we would have difficulties to
    say which path would be checked (we install to cross and not staging).
    Attempt to set an rpath when linking to mpfr/gmp. We pass --with-mpfr to the
    gcc-cross, patch the configure to add an -Wl,-rpath, to gmplibs, this gets
    set to GMPLIBS, which gets replaced to HOST_GMPLIBS in the Makefile inside the
    builddir, which will be used when linking the f951 utility.