apteryx/guile: Private copy of GNU Guile (https://git.savannah.gnu.org/cgit/guile.git/). @ add-srfi-151

Andy Wingo 9b9149a5bf Rework bootstrap to be reproducible		%!s(int64=2) %!d(string=hai) anos
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Makefile.am	9b9149a5bf Rework bootstrap to be reproducible	%!s(int64=2) %!d(string=hai) anos