Add additional KVP (Key Value Pair) protocol  messages to
enhance KVP functionality for Linux guests on Hyper-V. As part of this,
patch define an explicit version negoitiation message.
Reviewed-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>