As Travis Betak points out it accesses the wrong northbridge subfunction
now. Switch back to the old code.

Cc: "Travis Betak" <betak@mpdtxmail.amd.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>