Define a config variable BUILDTIME_EXTABLE_SORT to control build time
sorting of the kernel's exception table.

Patch Makefile to do the sorting when BUILDTIME_EXTABLE_SORT is
selected.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Link: http://lkml.kernel.org/r/1334872799-14589-4-git-send-email-ddaney.cavm@gmail.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>