Tools: hv: Gather DHCP information

Collect information on dhcp setting for the specified interface.
We invoke an external (Distro specific)  script to get this information.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>