superio/*: Deal with some chip.h special cases

While backing out the empty pc80 keyboard struct we encountered some
special cases where chip.h is used for other purposes. Deal with these
cases.

Change-Id: Ib11a46cfd14d050d5daa213623b9d8a401c06410
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/5621
Tested-by: build bot (Jenkins)
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>