DolphinWX: fix input bitmaps not working when background input is off

Source/Core/DolphinWX/UINeedsControllerState.h

@@ -0,0 +1,8 @@
+// Copyright 2017 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+void SetUINeedsControllerState(bool needs_controller_state);
+bool GetUINeedsControllerState();