Fix libvirt task check
Fix libvirt task check

The libvirt task checks for nova.compute_driver as
"nova.virt.libvirt.LibvirtDriver" instead of the modern
"libvirt.LibvirtDriver" causing Ursula to skip the
libvirt bits on compute hosts, effectively breaking
the nova compute service.

Change-Id: Ic476596623ab997a8c5a1ade50856d3f1419546a
(cherry picked from commit d3229fd9ce4ec16ec37ceac171357a90b09711ef)

sivakom/ursula,persistent-ursula/ursula,ryshah/ursula,sivakom/ursula,j2sol/ursula,nirajdp76/ursula,edtubillara/ursula,wupeiran/ursula,rongzhus/ursula,pgraziano/ursula,lihkin213/ursula,ryshah/ursula,fancyhe/ursula,pgraziano/ursula,knandya/ursula,wupeiran/ursula,nirajdp76/ursula,ddaskal/ursula,j2sol/ursula,ddaskal/ursula,edtubillara/ursula,lihkin213/ursula,rongzhus/ursula,twaldrop/ursula,blueboxgroup/ursula,pgraziano/ursula,masteinhauser/ursula,blueboxgroup/ursula,ryshah/ursula,channus/ursula,nirajdp76/ursula,narengan/ursula,j2sol/ursula,sivakom/ursula,twaldrop/ursula,masteinhauser/ursula,narengan/ursula,nirajdp76/ursula,wupeiran/ursula,ddaskal/ursula,edtubillara/ursula,lihkin213/ursula,edtubillara/ursula,j2sol/ursula,fancyhe/ursula,zrs233/ursula,blueboxgroup/ursula,zrs233/ursula,masteinhauser/ursula,fancyhe/ursula,panxia6679/ursula,channus/ursula,twaldrop/ursula,pgraziano/ursula,wupeiran/ursula,panxia6679/ursula,persistent-ursula/ursula,ryshah/ursula,knandya/ursula,channus/ursula,zrs233/ursula,channus/ursula,blueboxgroup/ursula,fancyhe/ursula,rongzhus/ursula,masteinhauser/ursula,persistent-ursula/ursula,ddaskal/ursula,rongzhus/ursula,twaldrop/ursula,lihkin213/ursula,narengan/ursula,narengan/ursula,knandya/ursula,zrs233/ursula,panxia6679/ursula,panxia6679/ursula,knandya/ursula,persistent-ursula/ursula