#31 Build failed on riscv64: cannot guess build type; you must specify one.

[Yuluo]

I am trying to package DMTCP for a Linux distro on riscv64 architecture.
Using the latest release, got a build error, configure: error: cannot guess build type; you must specify one.
It was caused by outdated config.guess and config.sub files in the latest release.
We can use autoreconf for temp resolution, but it would better to be updated.