Add Support USB ROM for SeaBIOS

by Wang Qing Pei for coreboot

SeaBIOS is the way to to boot all kinds of different operating systems.It support both PATA and SATA disk to boot various operating systems. It is also a coreboot payload that implements 16bit BIOS interrupts as they are needed by nearly all boot loaders today. One major feature that we're desperately lacking is USB stick/disk/cdrom booting from SeaBIOS. The main job may be add USB support for SeaBIOS which should be implemented as a PCI option rom.