ASoC: imx-audio-rpmsg: use module_rpmsg_driver to simplify the code

module_rpmsg_driver() makes the code simpler by eliminating
boilerplate code.
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20210602082610.3828408-1-yangyingliang@huawei.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/fsl/imx-audio-rpmsg.c

@@ -122,17 +122,7 @@ static struct rpmsg_driver imx_audio_rpmsg_driver = {
 	.remove		= imx_audio_rpmsg_remove,
 };
 
-static int __init imx_audio_rpmsg_init(void)
-{
-	return register_rpmsg_driver(&imx_audio_rpmsg_driver);
-}
-
-static void __exit imx_audio_rpmsg_exit(void)
-{
-	unregister_rpmsg_driver(&imx_audio_rpmsg_driver);
-}
-module_init(imx_audio_rpmsg_init);
-module_exit(imx_audio_rpmsg_exit);
+module_rpmsg_driver(imx_audio_rpmsg_driver);
 
 MODULE_DESCRIPTION("Freescale SoC Audio RPMSG interface");
 MODULE_AUTHOR("Shengjiu Wang <shengjiu.wang@nxp.com>");