rbd: Use proper error type
rbd: Use proper error type

andreabolognani/libvirt,eskultety/libvirt,eskultety/libvirt,datto/libvirt,olafhering/libvirt,nertpinx/libvirt,datto/libvirt,fabianfreyer/libvirt,VenkatDatta/libvirt,fabianfreyer/libvirt,VenkatDatta/libvirt,eskultety/libvirt,datto/libvirt,VenkatDatta/libvirt,jardasgit/libvirt,datto/libvirt,andreabolognani/libvirt,libvirt/libvirt,VenkatDatta/libvirt,jfehlig/libvirt,nertpinx/libvirt,eskultety/libvirt,jardasgit/libvirt,taget/libvirt,taget/libvirt,andreabolognani/libvirt,olafhering/libvirt,olafhering/libvirt,nertpinx/libvirt,nertpinx/libvirt,jfehlig/libvirt,zippy2/libvirt,jardasgit/libvirt,crobinso/libvirt,crobinso/libvirt,libvirt/libvirt,eskultety/libvirt,jfehlig/libvirt,fabianfreyer/libvirt,libvirt/libvirt,libvirt/libvirt,jfehlig/libvirt,VenkatDatta/libvirt,jardasgit/libvirt,taget/libvirt,fabianfreyer/libvirt,crobinso/libvirt,crobinso/libvirt,zippy2/libvirt,olafhering/libvirt,taget/libvirt,andreabolognani/libvirt,zippy2/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,zippy2/libvirt,datto/libvirt,andreabolognani/libvirt,nertpinx/libvirt,taget/libvirt