ARM: DAVINCI: Fix warning in tlv320aic23.c

Fix warning

drivers/i2c/chips/tlv320aic23.c: In function 'aic23_exit':
drivers/i2c/chips/tlv320aic23.c:671: warning: unused variable 'res'
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
Signed-off-by: Kevin Hilman <khilman@mvista.com>

drivers/i2c/chips/tlv320aic23.c

@@ -668,8 +668,6 @@ static int __init aic23_init(void)
 
 static void __exit aic23_exit(void)
 {
-	int res;
-
 	aic23_power_down();
 	i2c_del_driver(&aic23_driver);