[nostalgia/core/gba] Add wfi functions

src/nostalgia/core/gba/bios.hpp

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2016 - 2020 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+extern "C" {
+
+void nostalgia_core_halt();
+
+void nostalgia_core_stop();
+
+void nostalgia_core_wfi();
+
+void nostalgia_core_vblankwfi();
+
+}