x86: Decrease the level of some NUMA messages to KERN_DEBUG

Some NUMA messages in srat_32.c are confusing to users,
because they seem to indicate errors, while in fact they
reflect normal behaviour.

Decrease the level of these messages to KERN_DEBUG so that
they don't show up unnecessarily.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
LKML-Reference: <200909050107.45175.rjw@sisk.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>