Security updates for Thursday

Security updates have been issued by CentOS (firefox, flatpak, and systemd), Fedora (createrepo_c, dnf, dnf-plugins-core, dnf-plugins-extras, docker, libcomps, libdnf, and runc), Mageia (giflib, irssi, kernel, kernel-linus, libexif, poppler, tcpreplay, and zziplib), and SUSE (php5, procps, and qemu).