Remove virt.block_device._NoLegacy exception
Remove virt.block_device._NoLegacy exception

Nothing raised it.

Change-Id: Ieab1016ca24dd3f8505dcef41c402161886ca997

jianghuaw/nova,vmturbo/nova,rajalokan/nova,vmturbo/nova,vmturbo/nova,jianghuaw/nova,phenoxim/nova,gooddata/openstack-nova,alaski/nova,klmitch/nova,sebrandon1/nova,vmturbo/nova,rahulunair/nova,klmitch/nova,Juniper/nova,alaski/nova,gooddata/openstack-nova,jianghuaw/nova,Juniper/nova,mahak/nova,mahak/nova,cloudbase/nova,gooddata/openstack-nova,Juniper/nova,hanlind/nova,mahak/nova,cloudbase/nova,klmitch/nova,openstack/nova,Juniper/nova,mikalstill/nova,mikalstill/nova,rahulunair/nova,hanlind/nova,rajalokan/nova,openstack/nova,openstack/nova,jianghuaw/nova,klmitch/nova,rajalokan/nova,mikalstill/nova,sebrandon1/nova,cloudbase/nova,gooddata/openstack-nova,rajalokan/nova,phenoxim/nova,sebrandon1/nova,hanlind/nova,rahulunair/nova