Merge branch 'pci/yinghai-for-pci-root-bus-hotplug' into next

* pci/yinghai-for-pci-root-bus-hotplug:
  PCI/ACPI: Remove acpi_root_driver in reverse order
  PCI/ACPI: Delete host bridge _PRT during hot remove path
  PCI/ACPI: Make acpi_pci_root_remove() stop/remove pci root bus
  PCI: Add pci_stop_and_remove_root_bus()
  PCI/ACPI: Assign unassigned resource for hot-added root bus
  PCI: Move out pci_enable_bridges out of assign_unsigned_bus_res
  PCI: Move pci_rescan_bus() back to probe.c
  PCI: Separate out pci_assign_unassigned_bus_resources()