[3.13] gh-62184: Remove _pyio import of _io.FileIO (gh-134192) (gh-134436)

This was added in the add of `_io`, isn't used since bpo-21859 when a
`_pyio` implementation was added which defines `FileIO` lower down in
the file.
(cherry picked from commit 0a68068)

Co-authored-by: Cody Maloney <[email protected]>

Author: miss-islington

Lib/_pyio.py

@@ -654,8 +654,6 @@ def write(self, b):
         self._unsupported("write")
 
 io.RawIOBase.register(RawIOBase)
-from _io import FileIO
-RawIOBase.register(FileIO)
 
 
 class BufferedIOBase(IOBase):

Misc/NEWS.d/next/Library/2025-05-18-12-48-39.gh-issue-62184.y11l10.rst

@@ -0,0 +1,2 @@
+Remove import of C implementation of :class:`io.FileIO` from Python
+implementation which has its own implementation