rtc: convert rtc spi drivers to module_spi_driver

Factor out some boilerplate code for spi driver registration into
module_spi_driver.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Mark Jackson <mpfj@mimc.co.uk>
Cc: Dennis Aberilla <denzzzhome@yahoo.com>
Cc: Nikolaus Voss <n.voss@weinmann.de>
Cc: "Kim B. Heino" <Kim.Heino@bluegiga.com>
Cc: Raphael Assenat <raph@raphnet.net>
Cc: Chris Verges <chrisv@cyberswitching.com>
Cc: Magnus Damm <damm@opensource.se>
Cc: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-ds1390.c b/drivers/rtc/rtc-ds1390.c
index b038d2c..b0a99e1 100644
--- a/drivers/rtc/rtc-ds1390.c
+++ b/drivers/rtc/rtc-ds1390.c
@@ -175,17 +175,7 @@
 	.remove = __devexit_p(ds1390_remove),
 };
 
-static __init int ds1390_init(void)
-{
-	return spi_register_driver(&ds1390_driver);
-}
-module_init(ds1390_init);
-
-static __exit void ds1390_exit(void)
-{
-	spi_unregister_driver(&ds1390_driver);
-}
-module_exit(ds1390_exit);
+module_spi_driver(ds1390_driver);
 
 MODULE_DESCRIPTION("Dallas/Maxim DS1390/93/94 SPI RTC driver");
 MODULE_AUTHOR("Mark Jackson <mpfj@mimc.co.uk>");