The size of 'fontconfig' (as reported by `guix size`) decreases from
103.6 MiB to 92.1 MiB with this patch.  \o/

Short term I'm not sure what to do.  Perhaps we can add a
"glib-sans-util-linux" variant that does not propagate util-linux?  Or a
variant that propagates a util-linux-sans-binaries?

Diego: one work-around you can try in the meantime is to create a
~/setuid-programs, add it first on PATH, and symlink the required
binaries in there.  Sorry for the inconvenience!