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: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/wan/slic_ds26522.c

@@ -249,15 +249,4 @@ static struct spi_driver slic_ds26522_driver = {
 	.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);