configfs: don't bother with checks for mkdir/rmdir/unlink/symlink in root

just give root directory separate inode_operations without all those
methods...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/configfs/configfs_internal.h b/fs/configfs/configfs_internal.h
index ede857d..1b7fdc0 100644
--- a/fs/configfs/configfs_internal.h
+++ b/fs/configfs/configfs_internal.h
@@ -89,6 +89,7 @@
 extern const struct file_operations configfs_file_operations;
 extern const struct file_operations bin_fops;
 extern const struct inode_operations configfs_dir_inode_operations;
+extern const struct inode_operations configfs_root_inode_operations;
 extern const struct inode_operations configfs_symlink_inode_operations;
 extern const struct dentry_operations configfs_dentry_ops;