Revert "ppc/85xx/pci: fsl_pci_init: pcie agent mode support"

This reverts commit 70ed869e.

There isn't any need to modify the API for fsl_pci_init_port to pass the
status of host/agent(end-point) status.  We can determine that
internally to fsl_pci_init_port.  Revert the patch that makes the API
change.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>