Allow rbd backing stores
Allow rbd backing stores

Prevents libvirt from treating RBD backing stores as files. Without this
patch, creating a domain with a qcow2 overlay on an RBD would fail.

This patch essentially extends 9c7c4a4fc533598e59e9a0038ec783e61a38e664,
which allows nbd backing stores, to allow rbd backing stores.

trainstack/libvirt,nertpinx/libvirt,warewolf/libvirt,novel/fbsd-libvirt,jfehlig/libvirt,iam-TJ/libvirt,emaste/libvirt,wiedi/libvirt,datto/libvirt,andreabolognani/libvirt,trainstack/libvirt,jeckersb/libvirt,bjzhang/libvirt,rlaager/libvirt,emaste/libvirt,zippy2/libvirt,VenkatDatta/libvirt,andreabolognani/libvirt,wiedi/libvirt,VenkatDatta/libvirt,agx/libvirt,nertpinx/libvirt,andreabolognani/libvirt,libvirt/libvirt,bjzhang/libvirt,jeckersb/libvirt,eskultety/libvirt,warewolf/libvirt,trainstack/libvirt,elmarco/libvirt,bjzhang/libvirt,libvirt/libvirt,zippy2/libvirt,datto/libvirt,crobinso/libvirt,jfehlig/libvirt,olafhering/libvirt,crobinso/libvirt,warewolf/libvirt,fabianfreyer/libvirt,warewolf/libvirt,cbosdo/libvirt,rlaager/libvirt,zhlcindy/libvirt-1.1.4-maintain,jeckersb/libvirt,taget/libvirt,jeckersb/libvirt,shugaoye/libvirt,siboulet/libvirt-openvz,emaste/libvirt,siboulet/libvirt-openvz,warewolf/libvirt,libvirt/libvirt,fabianfreyer/libvirt,iam-TJ/libvirt,emaste/libvirt,fabianfreyer/libvirt,taget/libvirt,iam-TJ/libvirt,jeckersb/libvirt,warewolf/libvirt,zhlcindy/libvirt-1.1.4-maintain,emaste/libvirt,datto/libvirt,crobinso/libvirt,wiedi/libvirt,olafhering/libvirt,andreabolognani/libvirt,rlaager/libvirt,bjzhang/libvirt,jeckersb/libvirt,shugaoye/libvirt,VenkatDatta/libvirt,shugaoye/libvirt,nertpinx/libvirt,emaste/libvirt,wiedi/libvirt,siboulet/libvirt-openvz,datto/libvirt,wiedi/libvirt,cbosdo/libvirt,jfehlig/libvirt,jeckersb/libvirt,eskultety/libvirt,eskultety/libvirt,novel/fbsd-libvirt,elmarco/libvirt,cbosdo/libvirt,elmarco/libvirt,jardasgit/libvirt,zhlcindy/libvirt-1.1.4-maintain,VenkatDatta/libvirt,rlaager/libvirt,zippy2/libvirt,novel/fbsd-libvirt,zhlcindy/libvirt-1.1.4-maintain,andreabolognani/libvirt,agx/libvirt,siboulet/libvirt-openvz,trainstack/libvirt,fabianfreyer/libvirt,taget/libvirt,VenkatDatta/libvirt,iam-TJ/libvirt,jardasgit/libvirt,warewolf/libvirt,novel/fbsd-libvirt,novel/fbsd-libvirt,jfehlig/libvirt,shugaoye/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,novel/fbsd-libvirt,datto/libvirt,trainstack/libvirt,trainstack/libvirt,rlaager/libvirt,trainstack/libvirt,eskultety/libvirt,agx/libvirt,olafhering/libvirt,iam-TJ/libvirt,cbosdo/libvirt,taget/libvirt,zhlcindy/libvirt-1.1.4-maintain,novel/fbsd-libvirt,jardasgit/libvirt,jardasgit/libvirt,bjzhang/libvirt,crobinso/libvirt,eskultety/libvirt,libvirt/libvirt,shugaoye/libvirt,novel/fbsd-libvirt,nertpinx/libvirt,agx/libvirt,cbosdo/libvirt,taget/libvirt,emaste/libvirt,elmarco/libvirt,iam-TJ/libvirt,siboulet/libvirt-openvz,olafhering/libvirt,agx/libvirt,iam-TJ/libvirt,zippy2/libvirt,wiedi/libvirt,elmarco/libvirt,wiedi/libvirt,novel/fbsd-libvirt,nertpinx/libvirt