There were bugs in mmconfig access to PCI space, up to and
include 2.6.16-rc1. These prevented the sky2 driver from being
able to clear PCI express errors.

This patch makes the driver check (during probe), for errors
in PCI config access and fail.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>