This is confirmed to fix a hang due to PCI resource conflicts with
setting up the Cardbus bridge on old laptops with the 440MX chipsets.
Original report by Alessio Sangalli, lspci debugging help by Pekka
Enberg, and trial patch suggested by Daniel Ritz:

  "From the docs available i would _guess_ this thing is really similar
   to the 82443BX/82371AB combination.  at least the SMBus base address
   register is hidden at the very same place (32bit at 0x90 in function
   3 of the "south" brigde)"

The dang thing is largely undocumented, but the patch was corroborated
by Asit Mallick:

 "I am trying to find the register information. 440MX is an integration of
  440BX north-bridge without AGP and PIIX4E (82371EB).  PIIX4 quirk
  should cover the ACPI and SMBus related I/O registers."

and verified to fix the problem by Alessio.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>