Add ChangeLog entry

Add a ChangeLog entry for Jonathan Bennett's contribution which allows
loading symlinked certificates.
diff --git a/ChangeLog b/ChangeLog
index ef2e7b7..36e6393 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
+= mbed TLS 2.16.X branch released XXXX-XX-XX
+
+Bugfix
+   * Allow loading symlinked certificates. Fixes #3005. Reported and fixed
+     by Jonathan Bennett <JBennett@incomsystems.biz> via #3008.
+
 = mbed TLS 2.16.5 branch released xxxx-xx-xx
 
 Security