asm unexecutable stack

asm unexecutable stack

make stack not executable in assembled files

FIXES 125491

Change-Id: I396680b6877843201f6c07d5607385044abd5e74
Reviewed-on: http://gerrit.openafs.org/818
Reviewed-by: Simon Wilkinson <sxw@inf.ed.ac.uk>
Reviewed-by: Russ Allbery <rra@stanford.edu>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit 9bfd03d723a9cf17673f40513a7adde1d503bcbc)
Reviewed-on: http://gerrit.openafs.org/976