tools/hv: Fix /var subdirectory

Initial patch by Ben Hutchings <ben@decadent.org.uk>

We will install this in /usr, so it must use /var/lib for its state.
Only programs installed under /opt should use /var/opt.

Signed-off-by: Tomas Hozza <thozza@redhat.com>
Acked-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>