PCI: dwc: Disable outbound windows only for controllers using iATU

Some DWC-based controllers (e.g., pcie-al.c and pci-keystone.c, identified
by the fact that they override the default dw_child_pcie_ops) use their own
address translation approach instead of the DWC internal ATU (iATU).  For
those controllers, skip disabling the iATU outbound windows.

[bhelgaas: commit log, update multiple window comment]
Fixes: 458ad06c ("PCI: dwc: Ensure all outbound ATU windows are reset")
Link: https://lore.kernel.org/r/20220624143428.8334-4-Sergey.Semin@baikalelectronics.ru


Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>