[Check] Fix config docstring (#26222)

utils/check_config_docstrings.py

@@ -16,7 +16,6 @@
 import inspect
 import re
 
-from transformers import CTRLConfig
 from transformers.utils import direct_transformers_import
 
 
@@ -74,9 +73,7 @@ def get_checkpoint_from_config_class(config_class):
 def check_config_docstrings_have_checkpoints():
     configs_without_checkpoint = []
 
-    a = [CTRLConfig]
-
-    for config_class in a:
+    for config_class in list(CONFIG_MAPPING.values()):
         # Skip deprecated models
         if "models.deprecated" in config_class.__module__:
             continue