Clarify empty extra-info logging

train_util.py

@@ -87,6 +87,15 @@ def load_extra_info_types_file(path: str) -> list[int]:
         raise ValueError(f"Invalid extra info type id in {path}") from exc
 
 
+def format_extra_info_types(extra_info_types: Iterable[int] | None) -> str:
+    if extra_info_types is None:
+        return "all"
+    values = [int(x) for x in extra_info_types]
+    if not values:
+        return "none"
+    return str(values)
+
+
 def load_eid_file(path: str | Path) -> set[int]:
     file_path = Path(path)
     if not file_path.is_file():