Add a changelog entry for ECJPAKE to PMS KDF

Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/ChangeLog.d/ecjpake_to_pms.txt b/ChangeLog.d/ecjpake_to_pms.txt
new file mode 100644
index 0000000..4dd2075
--- /dev/null
+++ b/ChangeLog.d/ecjpake_to_pms.txt
@@ -0,0 +1,5 @@
+API changes
+   * Add an ad-hoc key derivation function handling ECJPAKE to PMS
+     calculation that can be used to derive the session secret in TLS 1.2,
+     as described in draft-cragie-tls-ecjpake-01. This can be achieved by
+     using PSA_ALG_TLS12_ECJPAKE_TO_PMS as the key derivation algorithm.