Fix PSA tests

The test framework has changed, but it did not cause any merge
conflicts. Still it affected new code in the tests.
diff --git a/tests/psa_crypto_helpers.h b/tests/psa_crypto_helpers.h
index 26d5623..3780d16 100644
--- a/tests/psa_crypto_helpers.h
+++ b/tests/psa_crypto_helpers.h
@@ -45,7 +45,7 @@
     /* If the test has already failed, don't overwrite the failure
      * information. Do keep the stats lookup above, because it can be
      * convenient to break on it when debugging a failure. */
-    if( msg != NULL && test_info.failed == 0 )
+    if( msg != NULL && test_info.result == TEST_RESULT_SUCCESS )
         test_fail( msg, line, file );
 
     return( msg == NULL );