ACPI / glue: Add .match() callback to struct acpi_bus_type

USB uses the .find_bridge() callback from struct acpi_bus_type
incorrectly, because as a result of the way it is used by USB every
device in the system that doesn't have a bus type or parent is
passed to usb_acpi_find_device() for inspection.

What USB actually needs, though, is to call usb_acpi_find_device()
for USB ports that don't have a bus type defined, but have
usb_port_device_type as their device type, as well as for USB
devices.

To fix that replace the struct bus_type pointer in struct
acpi_bus_type used for matching devices to specific subsystems
with a .match() callback to be used for this purpose and update
the users of struct acpi_bus_type, including USB, accordingly.
Define the .match() callback routine for USB, usb_acpi_bus_match(),
in such a way that it will cover both USB devices and USB ports
and remove the now redundant .find_bridge() callback pointer from
usb_acpi_bus.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 765398c..c31187d 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -71,9 +71,14 @@
 #ifdef CONFIG_ACPI
 #include <acpi/acpi_bus.h>
 
+static bool acpi_scsi_bus_match(struct device *dev)
+{
+	return dev->bus == &scsi_bus_type;
+}
+
 int scsi_register_acpi_bus_type(struct acpi_bus_type *bus)
 {
-        bus->bus = &scsi_bus_type;
+        bus->match = acpi_scsi_bus_match;
         return register_acpi_bus_type(bus);
 }
 EXPORT_SYMBOL_GPL(scsi_register_acpi_bus_type);