[coreboot] Inteltool patch v4

[Maciej Pijanka]

Hello

This is last version, includes detecting southbridge using
device_class not device location on bus as Stefan suggested, also will
tell if find more than one device with device_class 0x601 and notify
which one it used (it will be first but may depend on order of devices
inside structures returned by libpci).

Regards
Maciej