libhif.spec: Only use Recommends on Fedora >= 23
libhif.spec: Only use Recommends on Fedora >= 23

Since it doesn't exist in EL7, but I'd like to do CI/CD using the
upstream specfile.

(I may optionally teach rpmdistro-gitoverlay how to just drop
 these...)

edynox/libdnf,hughsie/libhif,rpm-software-management/libhif,Conan-Kudo/libhif,hughsie/libhif,rpm-software-management/libdnf,rpm-software-management/libdnf,rpm-software-management/libhif,rpm-software-management/libdnf,rpm-software-management/libhif,Conan-Kudo/libhif,hughsie/libhif,edynox/libdnf,Conan-Kudo/libhif,rpm-software-management/libhif,edynox/libdnf,edynox/libdnf,hughsie/libhif,rpm-software-management/libdnf,Conan-Kudo/libhif