32-bit detection by configure script on atom machines

[DanGrayson]

I've had a bug report from a user of Macaulay2 that indicates that the mpir 3.0.0 configure script thinks his machine is 64 bit, but it's actually 32 bit, and then "as" objects to the "mulq" instructions used by mpir during the build. (I think he'll able to work around it by passing ABI=32 to your configure script.)

Your configure script says this to him:

checking build system type... atom-pc-linux-gnu

Your (very old) script "config.guess" returns "atom-pc-linux-gnu". A more modern version of "config.guess" dated 2017-05-27 returns "i686-pc-linux-gnu".

Maybe all that's required is to update that script, along with "config.sub". The most recent one is dated 2020-01-01.