Revert "setup_board: make the gcc/glibc version stable by default, take 3"
Revert "setup_board: make the gcc/glibc version stable by default, take 3"

This reverts commit 19754342048a44304150981b2938f604751605e7

The tree is on fire: the x86 canaries and x86 generic full
bots are dying with internal gold link errors.
http://crosbug.com/26168

Only happens on new sdks, so we're shotgunning a few
suspicious revs and hoping for the best.

Change-Id: Iae05c876ff2a84f4a9f549f74b2ee7e0903f2b5a
Reviewed-on: https://gerrit.chromium.org/gerrit/15669
Commit-Ready: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>
Reviewed-by: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>
Tested-by: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>

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