watchdog: it87_wdt: remove useless function

Fix the following clang warning:

drivers/watchdog/it87_wdt.c:155:20: warning: unused function
'superio_outw' [-Wunused-function].
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/1618306460-57286-1-git-send-email-jiapeng.chong@linux.alibaba.comSigned-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

drivers/watchdog/it87_wdt.c

@@ -152,14 +152,6 @@ static inline int superio_inw(int reg)
 	return val;
 }
 
-static inline void superio_outw(int val, int reg)
-{
-	outb(reg++, REG);
-	outb(val >> 8, VAL);
-	outb(reg, REG);
-	outb(val, VAL);
-}
-
 /* Internal function, should be called after superio_select(GPIO) */
 static void _wdt_update_timeout(unsigned int t)
 {