Define RPMTAG_MODULARITYLABEL if rpm doesn't define it.
Define RPMTAG_MODULARITYLABEL if rpm doesn't define it.

This allows us to stay at an older rpm version.

rpm-software-management/libdnf,hughsie/libhif,hughsie/libhif,rpm-software-management/libdnf,rpm-software-management/libhif,rpm-software-management/libdnf,rpm-software-management/libdnf,rpm-software-management/libhif,rpm-software-management/libhif,hughsie/libhif,hughsie/libhif,rpm-software-management/libhif