fix the Makefile so it doesn't pollute sys.path

#4349 reviewed by Christian
diff --git a/Misc/NEWS b/Misc/NEWS
index acedeb1..45e965b 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -13,6 +13,9 @@
 Core and Builtins
 -----------------
 
+- Issue #4349: sys.path included a non-existent platform directory because of a
+  faulty Makefile.
+
 - Issue #3327: Don't overallocate in the modules_by_index list.
 
 - Issue #1721812:  Binary set operations and copy() returned the input type