_pyio: Fix TextIOWrapper constructor: os has no device_encoding() function

_io module doesn't call this function which was introduced in Python3.

Lib/_pyio.py

@@ -1436,11 +1436,6 @@ class TextIOWrapper(TextIOBase):
             raise TypeError("illegal newline type: %r" % (type(newline),))
         if newline not in (None, "", "\n", "\r", "\r\n"):
             raise ValueError("illegal newline value: %r" % (newline,))
-        if encoding is None:
-            try:
-                encoding = os.device_encoding(buffer.fileno())
-            except (AttributeError, UnsupportedOperation):
-                pass
         if encoding is None:
             try:
                 import locale