rtc-dev: Make RTC driver return ENOTTY instead of ENOIOCTLCMD

Prevent the RTC driver from returning ENOIOCTLCMD to userspace.
Signed-off-by: Thomas Hommel <thomas.hommel@gefanuc.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-dev.c

@@ -348,6 +348,8 @@ static int rtc_dev_ioctl(struct inode *inode, struct file *file,
 	case RTC_IRQP_SET:
 		if (ops->irq_set_freq)
 			err = rtc_irq_set_freq(rtc, rtc->irq_task, arg);
+		else
+			err = -ENOTTY;
 		break;
 
 #if 0