[PATCH] acpi_processor_latency_notifier(): UP warning fix

drivers/acpi/processor_idle.c:1112: warning: 'smp_callback' defined but not used

Cc: Len Brown <lenb@kernel.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>