TTY: serial: convert drivers/tty/serial/* to use module_platform_driver()

This patch converts the drivers in drivers/tty/serial/* to use the
module_platform_driver() macro which makes the code smaller and a bit
simpler.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jamie Iles <jamie@jamieiles.com>
Cc: Yoichi Yuasa <yuasa@linux-mips.org>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/tty/serial/timbuart.c b/drivers/tty/serial/timbuart.c
index e76c8b7..70f9749 100644
--- a/drivers/tty/serial/timbuart.c
+++ b/drivers/tty/serial/timbuart.c
@@ -513,20 +513,7 @@
 	.remove		= __devexit_p(timbuart_remove),
 };
 
-/*--------------------------------------------------------------------------*/
-
-static int __init timbuart_init(void)
-{
-	return platform_driver_register(&timbuart_platform_driver);
-}
-
-static void __exit timbuart_exit(void)
-{
-	platform_driver_unregister(&timbuart_platform_driver);
-}
-
-module_init(timbuart_init);
-module_exit(timbuart_exit);
+module_platform_driver(timbuart_platform_driver);
 
 MODULE_DESCRIPTION("Timberdale UART driver");
 MODULE_LICENSE("GPL v2");