mtd_blktrans_ops->release() should return void

Both existing instances always return 0 and even if they didn't,
the value would be lost on the way out.  Just don't bother...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/drivers/mtd/sm_ftl.c b/drivers/mtd/sm_ftl.c
index 8dd6ba5..f9d5615 100644
--- a/drivers/mtd/sm_ftl.c
+++ b/drivers/mtd/sm_ftl.c
@@ -1107,7 +1107,7 @@
 }
 
 /* outside interface: device is released */
-static int sm_release(struct mtd_blktrans_dev *dev)
+static void sm_release(struct mtd_blktrans_dev *dev)
 {
 	struct sm_ftl *ftl = dev->priv;
 
@@ -1116,7 +1116,6 @@
 	cancel_work_sync(&ftl->flush_work);
 	sm_cache_flush(ftl);
 	mutex_unlock(&ftl->mutex);
-	return 0;
 }
 
 /* outside interface: get geometry */