pre-test version of the mbedtls_ssl_conf_rng removal

Signed-off-by: Ben Taylor <ben.taylor@linaro.org>
diff --git a/library/ssl_client.c b/library/ssl_client.c
index be4d621..f8abfde 100644
--- a/library/ssl_client.c
+++ b/library/ssl_client.c
@@ -725,8 +725,7 @@
 #endif /* MBEDTLS_HAVE_TIME */
     }
 
-    ret = ssl->conf->f_rng(ssl->conf->p_rng,
-                           randbytes + gmt_unix_time_len,
+    ret = psa_generate_random(randbytes + gmt_unix_time_len,
                            MBEDTLS_CLIENT_HELLO_RANDOM_LEN - gmt_unix_time_len);
     return ret;
 }
@@ -867,8 +866,8 @@
     if (session_id_len != session_negotiate->id_len) {
         session_negotiate->id_len = session_id_len;
         if (session_id_len > 0) {
-            ret = ssl->conf->f_rng(ssl->conf->p_rng,
-                                   session_negotiate->id,
+
+            ret = psa_generate_random(session_negotiate->id,
                                    session_id_len);
             if (ret != 0) {
                 MBEDTLS_SSL_DEBUG_RET(1, "creating session id failed", ret);