superio/winbond/*: Provide common romstage component

Following the reasoning of:
cf7b498 superio/fintek/*: Factor out generic romstage component

Change-Id: I3e889c0305c012e7556a5dd348e7f1e1ba629a9d
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/5587
Tested-by: build bot (Jenkins)
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
4 files changed