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/block/z2ram.c b/drivers/block/z2ram.c
index b259040..64f941e 100644
--- a/drivers/block/z2ram.c
+++ b/drivers/block/z2ram.c
@@ -64,7 +64,6 @@
 
 static DEFINE_SPINLOCK(z2ram_lock);
 
-static struct block_device_operations z2_fops;
 static struct gendisk *z2ram_gendisk;
 
 static void do_z2_request(struct request_queue *q)
@@ -315,7 +314,7 @@
     return 0;
 }
 
-static struct block_device_operations z2_fops =
+static const struct block_device_operations z2_fops =
 {
 	.owner		= THIS_MODULE,
 	.open		= z2_open,