[NTOSKRNL]

[NTOSKRNL]
- Create a helper function named OpenRegistryHandlesFromSymbolicLink which opens handles to various paths associated with a symbolic link
- Store the Linked value in IoSetDeviceInterfaceState
- Implement checking if an interface is enabled by reading the Linked value
- Interfaces reported from IoGetDeviceInterfaces are only active ones now (unless the caller explicitly says that they want disabled ones too)

svn path=/trunk/; revision=47029