Fix issue #3547: ctypes is confused by bitfields of varying integer types

Reviewed by Fredrik Lundh and Skip Montanaro.
diff --git a/Misc/NEWS b/Misc/NEWS
index 0c22233..37bb634 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -15,6 +15,9 @@
 Library
 -------
 
+- Issue #3547: Fixed ctypes structures bitfields of varying integer
+  sizes.
+
 - Issue #3879: A regression in urllib.getproxies_enviroment was fixed.
 
 Build