[arm64] Fix jssp based spill slot accesses in Crankshaft

test/mjsunit/regress/regress-arm64-spillslots.js

+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax
+
+"use strict";
+
+function Message(message) {
+  this.message = message;
+}
+
+function Inlined(input) {
+  var dummy = arguments[1] === undefined;
+  if (input instanceof Message) {
+    return input;
+  }
+  print("unreachable, but we must create register allocation complexity");
+  return [];
+}
+
+function Process(input) {
+  var ret = [];
+  ret.push(Inlined(input[0], 1, 2));
+  return ret;
+}
+
+var input = [new Message("TEST PASS")];
+
+Process(input);
+Process(input);
+%OptimizeFunctionOnNextCall(Process);
+var result = Process(input);
+assertEquals("TEST PASS", result[0].message);