PCI: intel-gw: Drop manual DW PCIe controller version setup

Since the DW PCIe common code (dw_pcie_version_detect()) now reads the IP
core version directly from the hardware, there is no point manually setting
the version for controllers newer than v4.70a.

Remove the now-superfluous intel-gw code that sets struct dw_pcie.version.

Suggested-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220624143947.8991-7-Sergey.Semin@baikalelectronics.ru


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>