Remove openstack-nova-doc from openSUSE install

Follow change I8e7ba80124d8409410b03724ac6ab336355935e8 to remove
nova-doc also from openSUSE install, it's not needed and we do not
install doc packages anywhere.

Change-Id: I4832361dcc4a0705c9beba61bc97d4538a2ed8e0
Merge "Remove openstack-nova-doc from openSUSE install"