uio: convert drivers/uio/* to use module_platform_driver()

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

Cc: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Cc: Magnus Damm <damm@igel.co.jp>
Cc: Amit Chatterjee <amit.chatterjee@ti.com>
Cc: Pratheesh Gangadhar <pratheesh@ti.com>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/uio/uio_pdrv.c b/drivers/uio/uio_pdrv.c
index ff50595..72d3646 100644
--- a/drivers/uio/uio_pdrv.c
+++ b/drivers/uio/uio_pdrv.c
@@ -104,17 +104,7 @@
 	},
 };
 
-static int __init uio_pdrv_init(void)
-{
-	return platform_driver_register(&uio_pdrv);
-}
-
-static void __exit uio_pdrv_exit(void)
-{
-	platform_driver_unregister(&uio_pdrv);
-}
-module_init(uio_pdrv_init);
-module_exit(uio_pdrv_exit);
+module_platform_driver(uio_pdrv);
 
 MODULE_AUTHOR("Uwe Kleine-Koenig");
 MODULE_DESCRIPTION("Userspace I/O platform driver");