add host to vif.py set_config_* functions
add host to vif.py set_config_* functions

- This change extends the function signture
  of the vif.py set_config_* functions to
  optionally accepth the host object.
- This is required to support host specifc
  features that depend on the vif type chosen
  e.g. vhost-user and multiqueue

Change-Id: I9b116f64864863ade32a99fcda9051b60ff7fbde

Juniper/nova,openstack/nova,phenoxim/nova,gooddata/openstack-nova,Juniper/nova,gooddata/openstack-nova,vmturbo/nova,Juniper/nova,phenoxim/nova,mikalstill/nova,hanlind/nova,klmitch/nova,rajalokan/nova,openstack/nova,rajalokan/nova,jianghuaw/nova,jianghuaw/nova,hanlind/nova,mahak/nova,openstack/nova,rahulunair/nova,Juniper/nova,vmturbo/nova,rajalokan/nova,gooddata/openstack-nova,jianghuaw/nova,klmitch/nova,klmitch/nova,jianghuaw/nova,mikalstill/nova,vmturbo/nova,mahak/nova,vmturbo/nova,rahulunair/nova,gooddata/openstack-nova,rahulunair/nova,hanlind/nova,klmitch/nova,mikalstill/nova,mahak/nova,rajalokan/nova