Add Changelog entry

Signed-off-by: Paul Elliott <paul.elliott@arm.com>
diff --git a/ChangeLog.d/fix-tls-padbuf-zeroization b/ChangeLog.d/fix-tls-padbuf-zeroization
new file mode 100644
index 0000000..36451cb
--- /dev/null
+++ b/ChangeLog.d/fix-tls-padbuf-zeroization
@@ -0,0 +1,4 @@
+Security
+   * Fix a case where potentially sensitive information held in memory would not
+     be completely zeroized during TLS 1.2 handshake, in both server and client
+     configurations.