cros: Replace "TPM" with "secure module" for machines without TPM.

components/login/secure_module_util.h

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENT_LOGIN_SECURE_MODULE_UTIL_H_
+#define COMPONENT_LOGIN_SECURE_MODULE_UTIL_H_
+
+#include "components/login/login_export.h"
+
+namespace login {
+
+enum class SecureModuleUsed {
+  UNQUERIED,
+  CR50,
+  TPM,
+};
+
+SecureModuleUsed LOGIN_EXPORT GetSecureModuleUsed();
+
+// Querys if this machine is using Cr50. Caches the result to avoid to many
+// unnecessary IO calls.
+void LOGIN_EXPORT QuerySecureModuleUsed();
+
+}  // namespace login
+
+#endif  // COMPONENT_LOGIN_SECURE_MODULE_UTIL_H_