Reword changelog entry
diff --git a/ChangeLog b/ChangeLog
index 9b1230e..ace0c28 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -31,6 +31,8 @@
      Inserted as an enhancement for #1371
    * Add support for alternative CSR headers, as used by Microsoft and defined
      in RFC 7468. Found by Michael Ernst. Fixes #767.
+   * Re-enable certain interoperability tests in ssl-opt.sh which had previously
+     been disabled for lack of a sufficiently recent version of GnuTLS on the CI.
 
 = mbed TLS 2.16.0 branch released 2018-12-21