platform/x86: panasonic-laptop: reuse module_acpi_driver

There is a macro to register and unregister modules in simple cases, Let's use
it and clean up the driver.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>

drivers/platform/x86/panasonic-laptop.c

@@ -643,23 +643,6 @@ static int acpi_pcc_hotkey_add(struct acpi_device *device)
 	return result;
 }
 
-static int __init acpi_pcc_init(void)
-{
-	int result = 0;
-
-	if (acpi_disabled)
-		return -ENODEV;
-
-	result = acpi_bus_register_driver(&acpi_pcc_driver);
-	if (result < 0) {
-		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
-				  "Error registering hotkey driver\n"));
-		return -ENODEV;
-	}
-
-	return 0;
-}
-
 static int acpi_pcc_hotkey_remove(struct acpi_device *device)
 {
 	struct pcc_acpi *pcc = acpi_driver_data(device);
@@ -679,10 +662,4 @@ static int acpi_pcc_hotkey_remove(struct acpi_device *device)
 	return 0;
 }
 
-static void __exit acpi_pcc_exit(void)
-{
-	acpi_bus_unregister_driver(&acpi_pcc_driver);
-}
-
-module_init(acpi_pcc_init);
-module_exit(acpi_pcc_exit);
+module_acpi_driver(acpi_pcc_driver);