PCI: imx6: Configure PHY based on Root Complex or Endpoint mode

Pass PHY_MODE_PCIE_EP if the PCI controller operates in Endpoint (EP) mode,
and fix the Root Complex (RC) mode being hardcoded using a drvdata mode
check.

Fixes: 8026f2d8 ("PCI: imx6: Call common PHY API to set mode, speed, and submode")
Link: https://lore.kernel.org/r/20241119-pci_fixup_addr-v8-6-c4bfa5193288@nxp.com


Signed-off-by: Frank Li <Frank.Li@nxp.com>
[kwilczynski: commit log]
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Richard Zhu <hongxing.zhu@nxp.com>