Merge branch 'pci/controller/max-link-speed'

Merge branch 'pci/controller/max-link-speed'

- Add pcie_get_link_speed() to encapsulate and bounds-check
  pcie_link_speed[] accesses (Hans Zhang)

- Validate max-link-speed from DT in j721e, brcmstb, mediatek-gen3, rzg3s
  (where the actual controller constraints are known), and remove it from
  the generic OF DT accessor (Hans Zhang)

* pci/controller/max-link-speed:
  PCI: of: Remove max-link-speed generation validation
  PCI: controller: Validate max-link-speed
  PCI: j721e: Validate max-link-speed from DT
  PCI: dwc: Use pcie_get_link_speed() helper for safe array access
  PCI: Add pcie_get_link_speed() helper for safe array access