programs/ssl: Fix compile errors when MBEDTLS_HAVE_TIME is not defined

Signed-off-by: Raoul Strackx <raoul.strackx@fortanix.com>
[dja: add some more fixes, tweak title]
Signed-off-by: Daniel Axtens <dja@axtens.net>
diff --git a/programs/ssl/ssl_test_lib.h b/programs/ssl/ssl_test_lib.h
index ff02492..b3c4cfa 100644
--- a/programs/ssl/ssl_test_lib.h
+++ b/programs/ssl/ssl_test_lib.h
@@ -129,7 +129,9 @@
                const char *file, int line,
                const char *str );
 
+#if defined(MBEDTLS_HAVE_TIME)
 mbedtls_time_t dummy_constant_time( mbedtls_time_t* time );
+#endif
 
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
 /* If MBEDTLS_TEST_USE_PSA_CRYPTO_RNG is defined, the SSL test programs will use