Add NEWS entry for the various unsupported platforms.
diff --git a/Misc/NEWS b/Misc/NEWS
index e8e0a4a..8eef67b 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,13 @@
Core and Builtins
-----------------
+- Support for AtheOS has been completely removed from the code base. It was
+ disabled since Python 3.0.
+
+- Support for several legacy threading libraries has been disabled. These
+ libraries are: Mach C threads, SunOS LWP, GNU pth, Irix threads. Support code
+ will be entirely removed in 3.3.
+
- Peephole constant folding had missed UNARY_POSITIVE.
- Issue #1722344: threading._shutdown() is now called in Py_Finalize(), which