Staging: hv: Add Time Sync feature to hv_utils module.

The Time Sync feature synchronizes guest time to host UTC time after reboot,
and restore from saved/paused state.

Signed-off-by: Hank Janssen <hjanssen@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>