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/joystick/as5011.c b/drivers/input/joystick/as5011.c
index 6d6e741..3063464 100644
--- a/drivers/input/joystick/as5011.c
+++ b/drivers/input/joystick/as5011.c
@@ -355,14 +355,4 @@
 	.id_table	= as5011_id,
 };
 
-static int __init as5011_init(void)
-{
-	return i2c_add_driver(&as5011_driver);
-}
-module_init(as5011_init);
-
-static void __exit as5011_exit(void)
-{
-	i2c_del_driver(&as5011_driver);
-}
-module_exit(as5011_exit);
+module_i2c_driver(as5011_driver);