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/jz4740-adc.c b/drivers/mfd/jz4740-adc.c
index ef39528..83ef102 100644
--- a/drivers/mfd/jz4740-adc.c
+++ b/drivers/mfd/jz4740-adc.c
@@ -338,17 +338,7 @@
 	},
 };
 
-static int __init jz4740_adc_init(void)
-{
-	return platform_driver_register(&jz4740_adc_driver);
-}
-module_init(jz4740_adc_init);
-
-static void __exit jz4740_adc_exit(void)
-{
-	platform_driver_unregister(&jz4740_adc_driver);
-}
-module_exit(jz4740_adc_exit);
+module_platform_driver(jz4740_adc_driver);
 
 MODULE_DESCRIPTION("JZ4740 SoC ADC driver");
 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");