Fix error while removing memory.h usage
diff --git a/tests/suites/main_test.function b/tests/suites/main_test.function
index fae56f4..9ebd9c3 100644
--- a/tests/suites/main_test.function
+++ b/tests/suites/main_test.function
@@ -9,6 +9,10 @@
 #define polarssl_free       free
 #endif
 
+#if defined(POLARSSL_MEMORY_BUFFER_ALLOC_C)
+#include "polarssl/memory_buffer_alloc.h"
+#endif
+
 static int test_errors = 0;
 
 SUITE_PRE_DEP