#2 GNU config is too old to build on RISC-V

[Cryolitia]

Please consider update config.guess & config.sub, the newest version of them could successfully build cunit on Arch Linux.

This script, last modified 2013-06-10, has failed to recognize
the operating system you are using. It is advised that you
download the most up to date version of the config scripts from

  http://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.guess;hb=HEAD
and
  http://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.sub;hb=HEAD

If the version you run (./config.guess) is already up to date, please
send the following data and any information you think might be
pertinent to <config-patches@gnu.org> in order to provide the needed
information to handle your system.

config.guess timestamp = 2013-06-10

uname -m = riscv64
uname -r = 5.15.0-VF2-2.10.4-4
uname -s = Linux
uname -v = #1 SMP PREEMPT Sun Mar 19 03:29:51 CST 2023

/usr/bin/uname -p = unknown
/bin/uname -X     = 

hostinfo               = 
/bin/universe          = 
/usr/bin/arch -k       = 
/bin/arch              = 
/usr/bin/oslevel       = 
/usr/convex/getsysinfo = 

UNAME_MACHINE = riscv64
UNAME_RELEASE = 5.15.0-VF2-2.10.4-4
UNAME_SYSTEM  = Linux
UNAME_VERSION = #1 SMP PREEMPT Sun Mar 19 03:29:51 CST 2023
configure: error: cannot guess build type; you must specify one

Reported-by: https://archriscv.felixc.at/.status/log.htm?url=logs/cunit/cunit-2.1.3-4.log