Currently, if SeaBIOS is set as the payload, it gets rebuilt every single time we do a build. Change it to re-build just when there’s a config change. Change-Id: Ib141f2cbf8796d449172432bb30fa4806cf90328 Signed-off-by: Martin Roth <martinroth@google.com> Reviewed-on: https://review.coreboot.org/13948 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>