Backport #878 from trunk:
Fix building x86_64 on x86_64 (and hopefully all other *64 archs on the same *64).

/branches/1.2/scripts/build/cc_gcc.sh | 26 0 26 0 --------------------------
/branches/1.2/scripts/crosstool.sh | 14 14 0 0 ++++++++++++++
2 files changed, 14 insertions(+), 26 deletions(-)

# Compute x86_64-specific values

CT_DoArchValues() {

    # The architecture part of the tuple:

    CT_TARGET_ARCH="${CT_ARCH}"

}