Updated stage4 RISC-V image with RPM (and some broken bits)

For context, see the previous post

I’ve uploaded our latest stage4 to http://oirase.annexia.org/riscv/.

util-linux is still missing, so there’s no mount command and the filesystem comes up read-only.

RPM has been added, but there’s some sort of bug or configuration problem in libdb which means that RPM cannot read its own database (although the RPM database that has been written seems fine and can be read quite happily from an x86_64 machine). Still under investigation …