Merge branch 'pci/enumeration'

- Only read/write PCIe Link 2 registers for devices with Links and PCIe
  Capability version >= 2 (Maciej W. Rozycki)

- Revert a patch that cleared PCI_STATUS during enumeration because it
  broke Linux guests on Apple's virtualization framework (Bjorn Helgaas)

- Assign PCI domain IDs using IDAs so IDs can be easily reused after
  loading/unloading host bridge drivers (Pali Rohár)

- Fix pci_device_is_present(), which previously always returned "false" for
  VFs because their vendor ID is always 0xfff (Michael S. Tsirkin)

- Check for alloc failure in pci_request_irq() (Zeng Heng)

* pci/enumeration:
  PCI: Check for alloc failure in pci_request_irq()
  PCI: Fix pci_device_is_present() for VFs by checking PF
  PCI: Assign PCI domain IDs by ida_alloc()
  Revert "PCI: Clear PCI_STATUS when setting up device"
  PCI: Access Link 2 registers only for devices with Links