scripts: update config.sub

Latest from upstream config-patches repo. (No change to config.guess)

Signed-off-by: "David Holsgrove" <david.holsgrove@xilinx.com>
Message-Id: <f15b7c69c142e935391e.1350284600@localhost.localdomain>
Patchwork-Id: 191476

reporter_name="Alexander BIGGA"

reporter_url="http://sourceware.org/ml/crossgcc/2008-06/msg00031.html"

reporter_comment=""