PCI: dwc: Organize local variable usage

There are several places in the common DW PCIe code with incoherent local
variable usage: a variable is defined and initialized with a structure
field, but the structure pointer is dereferenced to access that field
anyway; the local variable is defined and initialized but either used just
once or not used afterwards in the main part of the subsequent method.  It
mainly concerns the pcie_port.dev field. Fix that in the relevant places.

Link: https://lore.kernel.org/r/20220624143428.8334-12-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>