Drivers: hv: vmbus: add numa_node to sysfs

Being able to find the numa_node for a device is useful for userspace
drivers (DPDK) and also for diagnosing performance issues.  This makes
vmbus similar to pci.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>