vfs: switch ->show_options() to struct dentry *

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index d93a3fa..63765d5 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -419,9 +419,9 @@
 	return 0;
 }
 
-static int ubifs_show_options(struct seq_file *s, struct vfsmount *mnt)
+static int ubifs_show_options(struct seq_file *s, struct dentry *root)
 {
-	struct ubifs_info *c = mnt->mnt_sb->s_fs_info;
+	struct ubifs_info *c = root->d_sb->s_fs_info;
 
 	if (c->mount_opts.unmount_mode == 2)
 		seq_printf(s, ",fast_unmount");