Move utils.h and utils.cc from runtime/vm to runtime/platform

runtime/vm/debuginfo_linux.cc

Index: runtime/vm/debuginfo_linux.cc
diff --git a/runtime/vm/debuginfo_linux.cc b/runtime/vm/debuginfo_linux.cc
index b11df1bce8ab17c1b8a6b8cf9d1163f3fe6efe10..35a7824e2e039444a701cc936cbe954d42bad526 100644
--- a/runtime/vm/debuginfo_linux.cc
+++ b/runtime/vm/debuginfo_linux.cc
@@ -1,12 +1,12 @@
-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/debuginfo.h"
 
+#include "platform/utils.h"
 #include "vm/gdbjit_linux.h"
 #include "vm/os.h"
-#include "vm/utils.h"
 #include "vm/thread.h"
 
 namespace dart {