gpio: Convert drivers to use module_pci_driver()

This patch converts the drivers in drivers/gpio/* to use
module_pci_driver() macro which makes the code smaller and a bit
simpler by having less boilerplate.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

drivers/gpio/gpio-ml-ioh.c

@@ -611,17 +611,7 @@ static struct pci_driver ioh_gpio_driver = {
 	.resume = ioh_gpio_resume
 };
 
-static int __init ioh_gpio_pci_init(void)
-{
-	return pci_register_driver(&ioh_gpio_driver);
-}
-module_init(ioh_gpio_pci_init);
-
-static void __exit ioh_gpio_pci_exit(void)
-{
-	pci_unregister_driver(&ioh_gpio_driver);
-}
-module_exit(ioh_gpio_pci_exit);
+module_pci_driver(ioh_gpio_driver);
 
 MODULE_DESCRIPTION("OKI SEMICONDUCTOR ML-IOH series GPIO Driver");
 MODULE_LICENSE("GPL");