Split up stackguard-macros.h into sysdeps directories

[Joseph S. Myers]

On Tue, 15 May 2012, Roland McGrath wrote:

> If it's only used inside elf/ and the #include is fixed to <> then the
> generic file can stay in elf/ rather than moving to sysdeps/generic/.  The
> file should get a comment saying it might be overridden by a sysdeps file.

It's not only used inside elf/.  This file is included by two tests, 
elf/tst-stackguard1.c and nptl/tst-stackguard1.c.

-- 
Joseph S. Myers
joseph@codesourcery.com