Rename warn_text to something a little more descriptive.
diff --git a/OpenSSL/_util.py b/OpenSSL/_util.py
index 9909250..8d59252 100644
--- a/OpenSSL/_util.py
+++ b/OpenSSL/_util.py
@@ -99,7 +99,7 @@
     text_type.__name__ + " for {0} is no longer accepted, use bytes"
 )
 
-def warn_text(label, obj):
+def text_to_bytes_and_warn(label, obj):
     """
     If ``obj`` is text, emit a warning that it should be bytes instead and try
     to convert it to bytes automatically.