Fix the NullPointerException in Status Info.

Fix bug 1964037 Phone states activity fail. It only happens in Zaku build. Zaku build overlay the device_info_status.xml under vendor/docomo and don't have CDMA related preference. Status.java will hit the NullPointerException when trying to remove the non-exist preferences.

	modified:   src/com/android/settings/deviceinfo/Status.java