[ACPI] [PATCH] update piix busmastering bugfix

[Dominik B. <de...@br...>]

This patch resolves the PIIX4 BMISX errata issue (getting an I/O port value 
of 0)  / #9 in the TBD list. Additionally, the C3 state does not get entered 
when busmastering is active. See errata #18 in the January '02 PIIX4 
specification update for why this is necessary.

To apply cleanly, please apply my "[PATCH] resolved: [ACPI] throttling 
trouble" and the "update [ACPII] [PATCH] lvl2-read to enable throttling with 
PIIX4" patches first. If you've missed them on the acpi-devel mailing list, 
you can find them on 
http://www.brodo.de/english/pub/acpi/throttling1.acpi.diff
http://www.brodo.de/english/pub/acpi/throttling2.acpi.diff

Dominik