Patch from:
https://github.com/knorrie/python-btrfs/commit/9f1698ce16b6ae15bf7b3f9f414e9f08dd052b79

From 9f1698ce16b6ae15bf7b3f9f414e9f08dd052b79 Mon Sep 17 00:00:00 2001
From: Hans van Kranenburg <hans@knorrie.org>
Date: Sun, 21 May 2023 17:44:15 +0200
Subject: [PATCH] ioctl: Fix documentation error in FeatureFlags

The free_space_tree flag is located in compat_ro_flags.
--- a/btrfs/ioctl.py
+++ b/btrfs/ioctl.py
@@ -1410,7 +1410,7 @@ class FeatureFlags(object):
         incompat_flags: mixed_backref|default_subvol|compress_lzo|big_metadata|extended_iref
         >>> features.incompat_flags & btrfs.ioctl.FEATURE_INCOMPAT_MIXED_GROUPS
         0
-        >>> features.incompat_flags & btrfs.ioctl.FEATURE_COMPAT_RO_FREE_SPACE_TREE
+        >>> features.compat_ro_flags & btrfs.ioctl.FEATURE_COMPAT_RO_FREE_SPACE_TREE
         1
 
     .. note::