powerpc/85xx: mpc85xx ADS: remove pci exclude

This code was reworked in commit,

905e75c4

This change removed the fsl_add_bridge() which originally was above
the addition of the pci_exclude_device function. I think the assumption was that
the pci_exclude_device would prevent changes to the bridge PCI config after
it's been added. It seems it wasn't fully tested on MPC85xx ADS because
if you move the fsl_add_bridge() the pci_exclude_device is set in the machine
description then you can never update the PCI Config since the exclude
prevents it. This disrupts things like DMA.

This issue was extensively debugged by David Beazley.

Cc: xe-kernel@external.cisco.com
Cc: dbeazley@cisco.com
Cc: dwalker@fifo99.com
Signed-off-by: Daniel Walker <danielwa@cisco.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>