ASoC: Convert tegra_spdif to use module_platform_driver()

Use the module_platform_driver() macro which makes
the code smaller and a bit simpler.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/tegra/tegra_spdif.c

@@ -352,17 +352,7 @@ static struct platform_driver tegra_spdif_driver = {
 	.remove = __devexit_p(tegra_spdif_platform_remove),
 };
 
-static int __init snd_tegra_spdif_init(void)
-{
-	return platform_driver_register(&tegra_spdif_driver);
-}
-module_init(snd_tegra_spdif_init);
-
-static void __exit snd_tegra_spdif_exit(void)
-{
-	platform_driver_unregister(&tegra_spdif_driver);
-}
-module_exit(snd_tegra_spdif_exit);
+module_platform_driver(tegra_spdif_driver);
 
 MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");
 MODULE_DESCRIPTION("Tegra SPDIF ASoC driver");