- update two more cpufreq-related sysfs files to the new interface
  code
- always store the new, user-requested policy in another struct
  cpufreq_policy so that we can safely fall back to the old one in
  case something fails (this equals the behaviour before Pat's patch)
- the kobject which was registered in cpufreq_add_dev was inside a variable
  private to this function -- so the whole cpufreq sysfs interface returned
  -EINVAL.