[PATCH] x86{-64}: Remove old hack that disabled mmconfig support on AMD systems.

Now that Greg implemented MCFG/_SEG support this shouldn't be needed
anymore

Cc: gregkh@suse.de

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