[PATCH] x86_64: Fix 32bit thread coredumps

When a register set is passed in don't try to fix up the pointer.

Noticed by Al Viro

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>