ACPI / hotplug: Fix acpi_bus_get_device() return value check

Since acpi_bus_get_device() returns a plain int and not acpi_status,
ACPI_FAILURE() should not be used for checking its return value.  Fix
that.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / hotplug: Fix PCI host bridge hot removal

Since the PCI host bridge scan handler does not set hotplug.enabled,
the check of it in acpi_bus_device_eject() effectively prevents the
root bridge hot removal from working after commit a3b1b1ef78cd
(ACPI / hotplug: Merge device hot-removal routines).  However, that
check is not necessary, because the other acpi_bus_device_eject()
users, acpi_hotplug_notify_cb and acpi_eject_store(), do the same
check by themselves before executing that function.

For this reason, remove the scan handler check from
acpi_bus_device_eject() to make PCI hot bridge hot removal work
again.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Fixes: a3b1b1ef78cd (ACPI / hotplug: Merge device hot-removal routines)
ACPI / PCI root: Clear driver_data before failing enumeration

If a PCI host bridge cannot be enumerated due to an error in
pci_acpi_scan_root(), its ACPI device object's driver_data field
has to be cleared by acpi_pci_root_add() before freeing the
object pointed to by that field, or some later acpi_pci_find_root()
checks that should fail may succeed and cause quite a bit of
confusion to ensue.

Fix acpi_pci_root_add() to clear device->driver_data before
returning an error code as appropriate.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Merge branch 'acpi-hotplug-next' into bleeding-edge

* acpi-hotplug-next:
  ACPI / PCI root: Clear driver_data before failing enumeration
  ACPI / hotplug: Fix PCI host bridge hot removal
  ACPI / hotplug: Fix acpi_bus_get_device() return value check