ACPI / scan: Revert scan handler check in acpi_bus_match()

Commit 9f29ab1 (ACPI / scan: do not match drivers against objects
having scan handlers) introduced a boot regression on Tony's
ia64 HP rx2600.  Tony says:

  "It panics with the message:

   Kernel panic - not syncing: Unable to find SBA IOMMU: Try a generic or DIG kernel

   [...] my problem comes from arch/ia64/hp/common/sba_iommu.c
   where the code in sba_init() says:

        acpi_bus_register_driver(&acpi_sba_ioc_driver);
        if (!ioc_list) {

   but because of this change we never managed to call ioc_init()
   so ioc_list doesn't get set up, and we die."

Revert commit 9f29ab1 to avoid this breakage and we'll fix the
problem it attempted to address later.

Reported-by: Tony Luck <tony.luck@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / video: Do not bind to device objects with a driver or scan handler

With the introduction of ACPI scan handlers, ACPI device objects
with an ACPI scan handler attached to them must not be bound to
an ACPI driver any more.  Unfortunately, however, the ACPI video
driver attempts to do just that if there is a _ROM ACPI control
method defined under a device object with an ACPI scan handler.

Prevent that from happening by making the video driver's "add"
routine check if the device object already has a driver or
ACPI scan handler attached to it and return an error code in
that case.  That is not sufficient, though, because
acpi_bus_driver_init() would then clear the device object's
driver_data that may be set by the scan handler attached to it,
so for the fix to work acpi_bus_driver_init() has to be modified
to leave driver_data as is on errors.

References: https://bugzilla.kernel.org/show_bug.cgi?id=58091
Reported-and-bisected-by: Dmitry S. Demin <dmitryy.demin@gmail.com>
Reported-and-tested-by: Jason Cassell <bluesloth600@gmail.com>
Tracked-down-by: Aaron Lu <aaron.lu@intel.com>
Cc: 3.9+ <stable@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Merge branch 'acpi-fixes-next' into bleeding-edge

* acpi-fixes-next:
  ACPI / video: Do not bind to device objects with a driver or scan handler
  ACPI / scan: Revert scan handler check in acpi_bus_match()