add changelog

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/ChangeLog.d/8825.txt b/ChangeLog.d/8825.txt
new file mode 100644
index 0000000..b7a2487
--- /dev/null
+++ b/ChangeLog.d/8825.txt
@@ -0,0 +1,6 @@
+Features
+   * mbedtls_psa_get_random() is always available as soon as
+     MBEDTLS_PSA_CRYPTO_C is enabled at build time and psa_crypto_init() is
+     called at runtime. This together with MBEDTLS_PSA_RANDOM_STATE can be
+     used as random number generator function(f_rng) and context (p_rng) in
+     legacy functions.