storage: backend: fs: Touch up coding style
storage: backend: fs: Touch up coding style

virStorageBackendFileSystemRefresh() used "cleanup" label just for error
exits and didn't meet libvirt's standard for braces in one case.

olafhering/libvirt,fabianfreyer/libvirt,fabianfreyer/libvirt,eskultety/libvirt,shugaoye/libvirt,rlaager/libvirt,nertpinx/libvirt,elmarco/libvirt,VenkatDatta/libvirt,olafhering/libvirt,jfehlig/libvirt,olafhering/libvirt,VenkatDatta/libvirt,taget/libvirt,libvirt/libvirt,andreabolognani/libvirt,jardasgit/libvirt,libvirt/libvirt,VenkatDatta/libvirt,fabianfreyer/libvirt,jfehlig/libvirt,andreabolognani/libvirt,shugaoye/libvirt,libvirt/libvirt,datto/libvirt,eskultety/libvirt,jardasgit/libvirt,zippy2/libvirt,nertpinx/libvirt,eskultety/libvirt,crobinso/libvirt,agx/libvirt,fabianfreyer/libvirt,elmarco/libvirt,agx/libvirt,shugaoye/libvirt,zippy2/libvirt,rlaager/libvirt,rlaager/libvirt,agx/libvirt,datto/libvirt,fabianfreyer/libvirt,agx/libvirt,jfehlig/libvirt,elmarco/libvirt,jfehlig/libvirt,zippy2/libvirt,shugaoye/libvirt,taget/libvirt,VenkatDatta/libvirt,zippy2/libvirt,andreabolognani/libvirt,libvirt/libvirt,jardasgit/libvirt,rlaager/libvirt,jardasgit/libvirt,olafhering/libvirt,andreabolognani/libvirt,VenkatDatta/libvirt,nertpinx/libvirt,agx/libvirt,elmarco/libvirt,elmarco/libvirt,andreabolognani/libvirt,datto/libvirt,shugaoye/libvirt,crobinso/libvirt,taget/libvirt,rlaager/libvirt,taget/libvirt,taget/libvirt,nertpinx/libvirt,datto/libvirt,eskultety/libvirt,eskultety/libvirt,crobinso/libvirt,crobinso/libvirt,nertpinx/libvirt,datto/libvirt,jardasgit/libvirt