Add optimization_mode attribute for procedures

Allowed modes: "none", "minimal", "size", "speed"
Currently: none == minimal and size == speed

src/checker.hpp

@@ -112,6 +112,7 @@ struct AttributeContext {
 	String  thread_local_model;
 	String  deprecated_message;
 	DeferredProcedure deferred_procedure;
+	u32 optimization_mode; // ProcedureOptimizationMode
 	struct TypeAtomOpTable *atom_op_table;
 };