drivers/video/fbdev/s3c2410fb.c: don't make debug world-writable.

We don't want random users to be able to spam the logs, and commit
37549e94c77a94a9c32b5ae3313a3801cb66adf9 (sysfs: disallow
world-writable files.) finally makes this a build error.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/drivers/video/fbdev/s3c2410fb.c b/drivers/video/fbdev/s3c2410fb.c
index 81af5a6..6796d9d 100644
--- a/drivers/video/fbdev/s3c2410fb.c
+++ b/drivers/video/fbdev/s3c2410fb.c
@@ -616,7 +616,7 @@
 	return len;
 }
 
-static DEVICE_ATTR(debug, 0666, s3c2410fb_debug_show, s3c2410fb_debug_store);
+static DEVICE_ATTR(debug, 0664, s3c2410fb_debug_show, s3c2410fb_debug_store);
 
 static struct fb_ops s3c2410fb_ops = {
 	.owner		= THIS_MODULE,