const: make block_device_operations const

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/cdrom/viocd.c b/drivers/cdrom/viocd.c
index 0fff646..57ca69e 100644
--- a/drivers/cdrom/viocd.c
+++ b/drivers/cdrom/viocd.c
@@ -177,7 +177,7 @@
 	return cdrom_media_changed(&di->viocd_info);
 }
 
-struct block_device_operations viocd_fops = {
+static const struct block_device_operations viocd_fops = {
 	.owner =		THIS_MODULE,
 	.open =			viocd_blk_open,
 	.release =		viocd_blk_release,