cc/gcc: cleanup the _or_later logic

So far, we've had a version always select appropriate _or_later option,
which in turn would select all previous _or_later options.

Because the dependencies on companion libs were cumulative, that was
working OK. But the upcoming 4.6 will no longer depend on libelf, so
we can't keep the cumulative scheme we've been using so far.

Have each release family select the corresponding dependencies, instead
of relying on selecting previous _or_later.

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

# This file adds functions to build the C library for bare metal (IE. none)

# Copyright 2008 Yann E. MORIN

# Licensed under the GPL v2. See COPYING in the root of this package

do_libc_get() {

    :

}

do_libc_extract() {

    :

}

do_libc_check_config() {

    :

}

do_libc_start_files() {

    :

}

do_libc() {

    :

}

do_libc_finish() {

    :

}