This tool has ~ 5 MiB and it's not needed for librsvg.so.
Fedora provides it in package librsvg-tools, Debian in librsvg-bin, Void Linux in librsvg-utils, SUSE in rsvg-convert. Since there's only a single utility/tool, rsvg-convert, and it's like this for a very long time, I think that rsvg-convert is the best option for the subpackage name.