Some BIOSes hide 'overflow' device (dev #6) for i82875P/PE chipsets.
The same happens for i82865P/PE. Add a quirk to enable this device.
This allows i82875 EDAC driver to bind to chipset's dev #6 and not
dev #0 as the latter is used by AGP driver.

On my laptop (i82865P based) ACPI code is disabling this device
again in \_SB.PCI0._CRS method (called at least at PNP init time).
This can be easily worked around by patching DSDT.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Michal Miroslaw <mirq-linux@rere.qmqm.pl>
Acked-by: Doug Thompson <norsk5@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>