Add NEWS entry

Author: vstinner

Misc/NEWS.d/next/C_API/2025-01-15-11-42-07.gh-issue-128863.C9MkB_.rst

@@ -0,0 +1,9 @@
+The following private functions are deprecated and planned for removal in
+Python 3.16:
+
+* :c:func:`!_PyBytes_Join`: use :c:func:`PyBytes_Join`.
+* :c:func:`!_PyThreadState_UncheckedGet`: use :c:func:`PyThreadState_GetUnchecked`.
+* :c:func:`!_Py_HashPointer`: use :c:func:`Py_HashPointer`.
+* :c:func:`!_Py_fopen_obj`: use :c:func:`Py_fopen`.
+
+Patch by Victor Stinner.