gnuchess: Support for new ppc64le arch

Hi Antonio Ceballos,

We are adding support for new ppc64le (IBM powerPC Little Endian)
architecture as part of which we are looking at all the packages that
need update.
I was looking at  gnuchess-6.1.0 tarball and was failed to build  on
ppc64le machine because of outdated config.guess.

Latest config.guess with ppc64le support is available at :
http://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.guess;hb=HEAD

Would it be possible for you to spin up a newer version of "gnuchess"
with latest config.guess ?
Alternatively, if you want us to send a patch to config.guess, we can do
so too.

I can help to validate the new release tarball of the "gnuchess" works
well by compiling on ppc64le machine.

Appreciate your response.

Thanks and Regards,
Jay Shankar