Fix ChangeLog

Author: mpg

ChangeLog

@@ -5,7 +5,7 @@ mbed TLS ChangeLog (Sorted per branch, date)
 Bugfix
    * Fix bug in certificate validation that caused valid chains to be rejected
      when the first intermediate certificate has pathLenConstraint=0. Found by
-     Nicholas Wilson. Introduced in mbed TLS 2.2.0. #280
+     Nicholas Wilson. Introduced in mbed TLS 2.1.4. #280
 
 = mbed TLS 2.1.3 released 2015-11-04