This patch adds machine check tainting.  When a handled machine check
occurs the oops gets a new 'M' flag.  This is useful to ignore machines
with hardware problems in oops reports.

On i386 a thermal failure also sets this flag.

Done for x86-64 and i386 so far.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>