Append logical PME/GPIO device. Fix MPU device number.

Append logical PME/GPIO device. Fix MPU device number.

A mainboard may require configuration of the superio pins to fully
support some features. Things like A20# gate, leds, fans, infra-red
and bootstrap jumpers may be configured and controlled through the
logical PME device.

Change-Id: I6e77ff0295806ba3dff339013f73d99c2961388f
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/289
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>