This patch avoids that a kernel warning appears when smp_processor_id() is
called with preempt debugging enabled.

Cc: James Smart <james.smart@broadcom.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>