Update library version to 2.15.0
diff --git a/ChangeLog b/ChangeLog
index d387815..9de8ee8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,6 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
-= mbed TLS x.xx.x branch released xxxx-xx-xx
+= mbed TLS 2.15.0 branch released 2018-11-23
 
 Features
    * Add an experimental build option, USE_CRYPTO_SUBMODULE, to enable use of