The ICH7 SPIBAR offset and registers are different from later generation. ICH8 has a different offset from later generation. ICH6 has no SPI controller. Change-Id: I7691bce619089b15805114047bcb1fd121a5722b Signed-off-by: Arthur Heymans <arthur@aheymans.xyz> Reviewed-on: https://review.coreboot.org/17978 Tested-by: build bot (Jenkins) Reviewed-by: Martin Roth <martinroth@google.com>