docs/sphinx: include kernel-doc script as a dependency

When we update the script we should rebuild the docs. Otherwise
breaking changes made to the kdoc script don't become apparent until
later.

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20250116160306.1709518-32-alex.bennee@linaro.org>

docs/sphinx/depfile.py

@@ -31,6 +31,9 @@ def get_infiles(env):
         for path in Path(static_path).rglob('*'):
             yield str(path)
 
+    # also include kdoc script
+    yield str(env.config.kerneldoc_bin[1])
+
 
 def write_depfile(app, exception):
     if exception: