Update version number to 2.6.0
diff --git a/ChangeLog b/ChangeLog
index d3ad3b9..227faed 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,6 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
-= mbed TLS x.x.x branch released xxxx-xx-xx
+= mbed TLS 2.6.0 branch released 2017-08-10
 
 Security
    * Fix authentication bypass in SSL/TLS: when authmode is set to optional,