rtc: ds1374: Remove unused variable

Remove unused variable 'res' and fix the following build warning:

drivers/rtc/rtc-ds1374.c:667:6: warning: unused variable 'res' [-Wunused-variable]
Reported-by: Olof's autobuilder <build@lixom.net>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

drivers/rtc/rtc-ds1374.c

@@ -664,8 +664,6 @@ static int ds1374_remove(struct i2c_client *client)
 {
 	struct ds1374 *ds1374 = i2c_get_clientdata(client);
 #ifdef CONFIG_RTC_DRV_DS1374_WDT
-	int res;
-
 	misc_deregister(&ds1374_miscdev);
 	ds1374_miscdev.parent = NULL;
 	unregister_reboot_notifier(&ds1374_wdt_notifier);