PCI: dwc: Drop enum dw_pcie_as_type in favor of PCIE_ATU_TYPE_MEM/IO

Previously dw_pcie_ep_set_bar() converted the BAR PCI_BASE_ADDRESS_SPACE
bit to the internal dw_pcie_as_type enum (DW_PCIE_AS_MEM, DW_PCIE_AS_IO)
and passed it down to dw_pcie_prog_inbound_atu(), which converted the enum
to the PCIE_ATU_TYPE_MEM/PCIE_ATU_TYPE_IO values needed to program the ATU
registers.

Simplify the code by dropping the dw_pcie_as_type enum and passing
PCIE_ATU_TYPE_MEM or PCIE_ATU_TYPE_IO directly.

Reorder inbound ATU function arguments to match the outbound functions,
with address-related parameters at the end.

[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20220624143947.8991-10-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>