binutils/binutils: don't install symlinks when in canadian

When building a canadian-cross, the binutils are not executable on
the build machine, so there is no point in installing the symlinks
in the gcc static/shared install dirs.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

 # Compute sparc-specific values

 CT_DoArchTupleValues() {

     # That's the only thing to override

     if [ "${CT_ARCH_64}" = "y" ]; then

         CT_TARGET_ARCH="${CT_ARCH}64"

     fi

 }