Fix test suite never executed due to an undefined symbol

MBEDTLS_SSL_SOME_SUITES_USE_MAC and MBEDTLS_SSL_SOME_SUITES_USE_TLS_CBC are
dependencies of defined in an SSL header, so this header needs to be
included here.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/tests/suites/test_suite_constant_time_hmac.function b/tests/suites/test_suite_constant_time_hmac.function
index 435e4b9..9d9aa3c 100644
--- a/tests/suites/test_suite_constant_time_hmac.function
+++ b/tests/suites/test_suite_constant_time_hmac.function
@@ -4,6 +4,7 @@
 #include <mbedtls/md.h>
 #include <constant_time_internal.h>
 #include "md_psa.h"
+#include <ssl_misc.h>
 
 #include <test/constant_flow.h>
 /* END_HEADER */