md: move freeing of badblocks.page into md_rdev_clear

This ensures that it is always freed - there were case where
we failed to free the page.

Reported-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/md.c b/drivers/md/md.c
index d557e55..ac99616 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -816,6 +816,8 @@
 		put_page(rdev->bb_page);
 		rdev->bb_page = NULL;
 	}
+	kfree(rdev->badblocks.page);
+	rdev->badblocks.page = NULL;
 }
 EXPORT_SYMBOL_GPL(md_rdev_clear);
 
@@ -2191,9 +2193,7 @@
 	sysfs_remove_link(&rdev->kobj, "block");
 	sysfs_put(rdev->sysfs_state);
 	rdev->sysfs_state = NULL;
-	kfree(rdev->badblocks.page);
 	rdev->badblocks.count = 0;
-	rdev->badblocks.page = NULL;
 	/* We need to delay this, otherwise we can deadlock when
 	 * writing to 'remove' to "dev/state".  We also need
 	 * to delay it due to rcu usage.
@@ -3325,7 +3325,6 @@
 	if (rdev->bdev)
 		unlock_rdev(rdev);
 	md_rdev_clear(rdev);
-	kfree(rdev->badblocks.page);
 	kfree(rdev);
 	return ERR_PTR(err);
 }