gcc: update to 7.1 with tools * src/build-gcc.mk: update version 7.1.0 * src/cloog.mk: update 0.18.4 * src/gmp.mk: update 6.1.2 * src/isl.mk: update 0.16.1, add no-undefined flag * src/mpfr.mk: update 3.1.6 * src/native-gcc.mk: update 7.1.0 * src/isl-1-fixes.patch: removed file * dist-files.mk: remove reference to patch files, add mingw-w64 patch * src/build-gcc-1-mingw-float.patch: removed patch * src/native-gcc-1-mingw-float.patch: removed patch * src/build-gcc-2-intrinsics.patch: removed patch * src/native-gcc-2-intrinsics.patch: removed patch * src/mingw-w64.mk: update to 5.0.2 * src/gcc-1-mingw-float.patch: remove patch * src/gcc-2-darwin-no-pie.patch: remove patch * src/mingw-w64-2-pthreads.patch: new file * src/pthreads.mk: apply mingw patches to mingw sources before running configure

1cab2860069ea9401ff3f28f1fd9654bc777026b release-4-0-0
a047bc8d7910849a3ddcb4d1856ce3dd2b912aa4 octave-4.0.1-binary
e622765c49c736f6e8e4627310a59f1c49fae283 octave-release-4.2.0