Fix tokenizer for XLMRobertaXL (#19004)

Co-authored-by: ydshieh <ydshieh@users.noreply.github.com>

src/transformers/models/auto/tokenization_auto.py

@@ -271,7 +271,13 @@ else:
                     "XLMRobertaTokenizerFast" if is_tokenizers_available() else None,
                 ),
             ),
-            ("xlm-roberta-xl", ("RobertaTokenizer", "RobertaTokenizerFast" if is_tokenizers_available() else None)),
+            (
+                "xlm-roberta-xl",
+                (
+                    "XLMRobertaTokenizer" if is_sentencepiece_available() else None,
+                    "XLMRobertaTokenizerFast" if is_tokenizers_available() else None,
+                ),
+            ),
             (
                 "xlnet",
                 (

src/transformers/models/xlm_roberta_xl/modeling_xlm_roberta_xl.py

@@ -54,7 +54,7 @@ logger = logging.get_logger(__name__)
 
 _CHECKPOINT_FOR_DOC = "xlm-roberta-xlarge"
 _CONFIG_FOR_DOC = "XLMRobertaXLConfig"
-_TOKENIZER_FOR_DOC = "RobertaTokenizer"
+_TOKENIZER_FOR_DOC = "XLMRobertaTokenizer"
 
 XLM_ROBERTA_XL_PRETRAINED_MODEL_ARCHIVE_LIST = [
     "facebook/xlm-roberta-xl",