headers: Add MsvAvSingleHost in MSV1_0_AVID enum.

MsvAvSingleHost present in MS-NLMP specifications[1] but not in WinSDK
[1]: https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-nlmp/

Signed-off-by: Biswapriyo Nath <nathbappai@gmail.com>
Signed-off-by: Liu Hao <lh_mouse@126.com>