ALSA: Convert at73c213 to module_spi_driver

This patch converts at73c213 to use the module_spi_driver()
macro which makes the code smaller and a bit simpler.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/spi/at73c213.c b/sound/spi/at73c213.c
index 4dd051b..c6500d0 100644
--- a/sound/spi/at73c213.c
+++ b/sound/spi/at73c213.c
@@ -1112,17 +1112,7 @@
 	.remove		= __devexit_p(snd_at73c213_remove),
 };
 
-static int __init at73c213_init(void)
-{
-	return spi_register_driver(&at73c213_driver);
-}
-module_init(at73c213_init);
-
-static void __exit at73c213_exit(void)
-{
-	spi_unregister_driver(&at73c213_driver);
-}
-module_exit(at73c213_exit);
+module_spi_driver(at73c213_driver);
 
 MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
 MODULE_DESCRIPTION("Sound driver for AT73C213 with Atmel SSC");