southbridge/sb800: Strip obsolete commentary

Change-Id: I5cd9e1fcf197eae966be710b2ab24f49c6885eb0
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/5529
Tested-by: build bot (Jenkins)
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>