[coreboot] Multiple payloads support?

[Zheng Bao]

Hi, all,
I am trying to integrate SeaBIOS and another payload(coreinfo, nvramcui)
into final image.

After a quick code checking, current code in repo does not support multiple payload, does it?

I want to let Coreboot load and run nvramcui first. The user can decide to change the
CMOS setting or not. If user want to save the setting, the system need to reboot. If user wants
to give up the change, the system goes out of the nvramcui and goes into SeaBIOS. Just like 
other IBV's BIOS.

Did anyone do this job before? Any suggestion?

Zheng