ACPI: catch calls of acpi_driver_data on pointer of wrong type

Catch attempts to use of acpi_driver_data on pointers of wrong type.

akpm: rewritten to use proper C typechecking and remove the
"function"-used-as-lvalue thing.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index ee68ac5..2894616 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -818,7 +818,7 @@
 	pr->handle = device->handle;
 	strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
 	strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
-	acpi_driver_data(device) = pr;
+	device->driver_data = pr;
 
 	return 0;
 }