[coreboot] mcp55_fadt patch to fix Microsoft Windows BSOD 0x000000A5 (0x00000011, 0x00000006 ....)

[Stefan Reinauer]

* David Robinson <drobinson at bluechiptechnology.co.uk> [101209 10:40]:
> Hi,
> 
>  
> 
> The attached patch fixes a problem preventing Windows XP / 7 from booting with
> bug check error A5 (0x00000011, 0x00000006) on the Gigabyte GA-M57SLI- S4
> board. Microsoft documentation states that this bug check occurs because,
> “SCI_EN never becomes set in PM1 Control Register”. This patch sets the SCI_EN
> bit. The patch applies to any board featuring the MCP55 south bridge.

Wouldn't the right way to fix this be to actually implement the
acpi_enable/acpi_disable commands on smi_cmd?

Stefan