Input: convert I2C drivers to use module_i2c_driver()

This patch converts the drivers in drivers/input/* to use the
module_i2c_driver() macro which makes the code smaller and a bit
simpler.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/touchscreen/st1232.c b/drivers/input/touchscreen/st1232.c
index 8825fe3..cbbf71b 100644
--- a/drivers/input/touchscreen/st1232.c
+++ b/drivers/input/touchscreen/st1232.c
@@ -268,17 +268,7 @@
 	},
 };
 
-static int __init st1232_ts_init(void)
-{
-	return i2c_add_driver(&st1232_ts_driver);
-}
-module_init(st1232_ts_init);
-
-static void __exit st1232_ts_exit(void)
-{
-	i2c_del_driver(&st1232_ts_driver);
-}
-module_exit(st1232_ts_exit);
+module_i2c_driver(st1232_ts_driver);
 
 MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>");
 MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver");