net: wan: slic_ds26522: Use module_spi_driver to simplify the code

module_spi_driver() makes the code simpler by eliminating
boilerplate code.

Signed-off-by: Wei Yongjun <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/wan/slic_ds26522.c

···
 	.id_table = slic_ds26522_id,
 };
 
-static int __init slic_ds26522_init(void)
-{
-	return spi_register_driver(&slic_ds26522_driver);
-}
-
-static void __exit slic_ds26522_exit(void)
-{
-	spi_unregister_driver(&slic_ds26522_driver);
-}
-
-module_init(slic_ds26522_init);
-module_exit(slic_ds26522_exit);
+module_spi_driver(slic_ds26522_driver);