mfd: Convert MFD drivers to use module_platform_driver

Factors out some boilerplate code for drivers doing the default thing
for platform driver registration. Drivers using platform_driver_probe
or an initcall other than module_init can't be converted.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/pcf50633-adc.c b/drivers/mfd/pcf50633-adc.c
index aed0d2a..3927c17 100644
--- a/drivers/mfd/pcf50633-adc.c
+++ b/drivers/mfd/pcf50633-adc.c
@@ -249,17 +249,7 @@
 	.remove = __devexit_p(pcf50633_adc_remove),
 };
 
-static int __init pcf50633_adc_init(void)
-{
-	return platform_driver_register(&pcf50633_adc_driver);
-}
-module_init(pcf50633_adc_init);
-
-static void __exit pcf50633_adc_exit(void)
-{
-	platform_driver_unregister(&pcf50633_adc_driver);
-}
-module_exit(pcf50633_adc_exit);
+module_platform_driver(pcf50633_adc_driver);
 
 MODULE_AUTHOR("Balaji Rao <balajirrao@openmoko.org>");
 MODULE_DESCRIPTION("PCF50633 adc driver");