glasm: Add GLASM backend infrastructure

src/shader_recompiler/backend/glasm/emit_context.h

@@ -0,0 +1,21 @@
+// Copyright 2021 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <string>
+
+#include "shader_recompiler/backend/glasm/reg_alloc.h"
+
+namespace Shader::Backend::GLASM {
+
+class EmitContext {
+public:
+    std::string code;
+    RegAlloc reg_alloc;
+
+private:
+};
+
+} // namespace Shader::Backend::GLASM