sky2: don't use AER routines

Using PCIE advanced error recovery stuff creates more user problems than it's worth.
The AER stuff depends on MMCONFIG and in many configurations it just doesn't work.
Plus it doesn't add any real functionality to the driver. The sky2
driver handles its own errors fine as is.

This reverts 555382cb



Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>