i2c/busses: Use module_platform_driver()

Convert the drivers in drivers/i2c/busses/* to use the
module_platform_driver() macro which makes the code smaller and a bit
simpler.

Cc: Ben Dooks <ben-linux@fluff.org>
Acked-by: Jochen Friedrich <jochen@scram.de>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Manuel Lauss <manuel.lauss@googlemail.com>
Cc: Barry Song <21cnbao@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Yong Zhang <yong.zhang0@gmail.com>
Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/i2c/busses/i2c-pca-platform.c b/drivers/i2c/busses/i2c-pca-platform.c
index ace6799..2adbf1a 100644
--- a/drivers/i2c/busses/i2c-pca-platform.c
+++ b/drivers/i2c/busses/i2c-pca-platform.c
@@ -286,20 +286,8 @@
 	},
 };
 
-static int __init i2c_pca_pf_init(void)
-{
-	return platform_driver_register(&i2c_pca_pf_driver);
-}
-
-static void __exit i2c_pca_pf_exit(void)
-{
-	platform_driver_unregister(&i2c_pca_pf_driver);
-}
+module_platform_driver(i2c_pca_pf_driver);
 
 MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
 MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
 MODULE_LICENSE("GPL");
-
-module_init(i2c_pca_pf_init);
-module_exit(i2c_pca_pf_exit);
-