Add ChangeLog entry for Microblaze fix
diff --git a/ChangeLog b/ChangeLog
index 2d33641..bf6a18f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -5,6 +5,8 @@
 Bugfix
    * Fix redundant declaration of mbedtls_ssl_list_ciphersuites. Raised by
      TrinityTonic. #1359.
+   * Fix an issue with MicroBlaze support in bn_mul.h which was causing the
+     build to fail. Found by zv-io. Fixes #1651.
 
 Changes
    * Support TLS testing in out-of-source builds using cmake. Fixes #1193.