libc: get rid of libc_finish

At long last, we no longer have any libc that requries a libc_finish.
Yeah!

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

# Compute Alpha-specific values

CT_DoArchTupleValues () {

    # The architecture part of the tuple:

    CT_TARGET_ARCH="${CT_ARCH}${CT_ARCH_ALPHA_VARIANT}"

}