x86, mtrr: Kill over the top warn

Fixes bugzilla: http://bugzilla.kernel.org/show_bug.cgi?id=12558
Fixes bugzilla: http://bugzilla.kernel.org/show_bug.cgi?id=12317



(and if this really needed to be a warn you'd be responding to the bugs left
in bugzilla from it...)

Signed-off-by: Alan Cox <alan@linux.intel.com>
LKML-Reference: <20100208100239.2568.2940.stgit@localhost.localdomain>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>