Update Changelog for recent contribution
diff --git a/ChangeLog b/ChangeLog
index e904eb8..d44463f 100644
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+++ b/ChangeLog
@@ -10,6 +10,8 @@
      https://dl.acm.org/citation.cfm?id=2714625
 
 Features
+   * Improve ECC performance by using more efficient doubling formulas
+     (contributed by Peter Dettman).
    * Add x509_crt_verify_info() to display certificate verification results.
    * Add support for reading DH parameters with privateValueLength included
      (contributed by Daniel Kahn Gillmor).