Add changelog entry

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/ChangeLog.d/mingw.txt b/ChangeLog.d/mingw.txt
new file mode 100644
index 0000000..ac4e741
--- /dev/null
+++ b/ChangeLog.d/mingw.txt
@@ -0,0 +1,4 @@
+Bugfix
+   * Fix compilation error with mingw32. Fixed by Cameron Cawley in #4211.
+   * Fix compilation error when using C++ Builder on Windows. Reported by
+     Miroslav Mastny in #4015.