Revert "LibJS: Add StackFrame to avoid indirection in VM register access"

This reverts commit 36bb2824a6.

Although this was faster on my M3 MacBook Pro, other Apple machines
disagree, including our benchmark runner. So let's revert it.

Libraries/LibJS/Bytecode/Interpreter.h

@@ -56,6 +56,9 @@ public:
         return m_registers_and_constants_and_locals_arguments.data()[r.index()];
     }
 
+    [[nodiscard]] Value get(Operand) const;
+    void set(Operand, Value);
+
     Value do_yield(Value value, Optional<Label> continuation);
     void do_return(Value value)
     {