remove RNG parameters from SSL API's

Signed-off-by: Ben Taylor <ben.taylor@linaro.org>
diff --git a/programs/ssl/dtls_server.c b/programs/ssl/dtls_server.c
index 6430ed2..e881c91 100644
--- a/programs/ssl/dtls_server.c
+++ b/programs/ssl/dtls_server.c
@@ -216,8 +216,7 @@
         goto exit;
     }
 
-    if ((ret = mbedtls_ssl_cookie_setup(&cookie_ctx,
-                                        mbedtls_ctr_drbg_random, &ctr_drbg)) != 0) {
+    if ((ret = mbedtls_ssl_cookie_setup(&cookie_ctx)) != 0) {
         printf(" failed\n  ! mbedtls_ssl_cookie_setup returned %d\n\n", ret);
         goto exit;
     }