PCI: dwc: Validate iATU outbound mappings against hardware constraints

Make __dw_pcie_prog_outbound_atu() check the requested region base and size
against what the hardware can support.  Return error if the region is not
correctly aligned or of a supported size.

[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20220624143947.8991-14-Sergey.Semin@baikalelectronics.ru


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