x86_64 only delivers signals in the SA_INFO style, whether you ask
for it or not.  This patch adds a config option which says whether
the arch is SA_INFO-only or not, and ifdefs out the sigcontext
signal delivery if so.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>