[ACPI] Bind PCI devices with ACPI devices

Implement the framework for binding physical devices
with ACPI devices. A physical bus like PCI bus
should create a 'acpi_bus_type', with:

.find_device:
        For device which has parent such as normal PCI devices.

.find_bridge:
        It's for special devices, such as PCI root bridge
	or IDE controller.  Such devices generally haven't a
	parent or ->bus. We use the special method
	to get an ACPI handle.

Uses new field in struct device: firmware_data

http://bugzilla.kernel.org/show_bug.cgi?id=4277

Signed-off-by: David Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

include/linux/device.h

@@ -269,8 +269,10 @@ struct device {
 	struct device_driver *driver;	/* which driver has allocated this
 					   device */
 	void		*driver_data;	/* data private to the driver */
-	void		*platform_data;	/* Platform specific data (e.g. ACPI,
-					   BIOS data relevant to device) */
+	void		*platform_data;	/* Platform specific data, device
+					   core doesn't touch it */
+	void		*firmware_data; /* Firmware specific data (e.g. ACPI,
+					   BIOS data),reserved for device core*/
 	struct dev_pm_info	power;
 
 	u64		*dma_mask;	/* dma mask (if dma'able device) */