Add missing ChangeLog entry

Signed-off-by: Janos Follath <janos.follath@arm.com>
diff --git a/ChangeLog b/ChangeLog
index 057882e..3013818 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -12,6 +12,8 @@
 Bugfix
    * Fix compilation failure when both MBEDTLS_SSL_PROTO_DTLS and
      MBEDTLS_SSL_HW_RECORD_ACCEL are enabled.
+   * Fix a function name in a debug message. Contributed by Ercan Ozturk in
+     #3013.
 
 = mbed TLS 2.16.5 branch released 2020-02-20