install-guides: suse: Update nova-compute section
install-guides: suse: Update nova-compute section

Adds missing dependency 'libvirt' to installation command. For suse
related packages, libvirt is not installed by default.

Change-Id: I685cad41cf61f80c7d98b02ebe67414fe04c83fa

openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,potsmaster/openstack-manuals,openstack/openstack-manuals,Akasurde/openstack-manuals,openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,kairoaraujo/openstack-manuals,potsmaster/openstack-manuals,openstack/openstack-manuals,saeki-masaki/openstack-manuals,kairoaraujo/openstack-manuals,Akasurde/openstack-manuals,saeki-masaki/openstack-manuals