Update link to virtio-win webpage
Update link to virtio-win webpage

The link has moved.

Change-Id: I061acde650ad0bb2197410c48b110524370bb35d
Signed-off-by: Nicolas Bock <4ad6fd604400c7892c7a2cb53bf674987bcaa405@suse.com>

openstack/openstack-manuals,openstack/openstack-manuals,openstack/openstack-manuals,openstack/openstack-manuals