- Always force AHCI mode on a ATI/AMD SB600/700/800 SATA controller. These

- Always force AHCI mode on a ATI/AMD SB600/700/800 SATA controller.  These
controllers may be configured as legacy IDE mode by modifying subclass and
progif without actually changing PCI device IDs.  Instead of complicating
code, we always force AHCI mode while probing.  Also we restore AHCI mode
while resuming per ATI/AMD register programming/requirement guides.
- Fix SB700/800 "combined" mode.  Unlike SB600, this PATA controller can
combine two SATA ports and emulate one PATA channel as primary or secondary
depending on BIOS configuration.  When the combined mode is disabled, this
channel disappears and it works just like SB600 PATA controller, however.
- Add more PCI device IDs for SB700/800 and adjust device descriptions.
SB800 shares the same PCI device IDs and added two more SATA IDs.