[POWERPC] 86xx: Created quirk_fsl_pcie_transparent() to initialize bridge resources.

The Freescale PCI-e RC poses as a transparent bridge, but does not
implement the IO_BASE or IO_LIMIT registers in the config space.  This
means that the code which initializes the bridge resources ends up
setting the IO resources erroneously.  Add quick_fsl_pcie_transparent()
to handle this.

This change sets RC of mpc8641 to be a transparent bridge
for legacy I/O access and initializes the RC bridge resources
from the device tree.

Signed-off-by: Zhang Wei <wei.zhang@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>