Don't pass CR2 address on alignment faults.  They report the address of the
last page fault, which is a information leak.

Fix this for i386 and x86-64 by passing 0 instead.

Pointed out by Zachary Amsden <zach@vmware.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>