Python 3.x: do not regenerate _sysconfigdata

This commit fixes several issues:

- as reported in https://github.com/NixOS/nixpkgs/issues/24924 it was
possible that the file _sysconfigdata.pyc was generated after the actual
build of the CPython interpreter. We forgot to regenerate that file
during the build. This is now fixed

- the expression of the 3.3 interpreter now also includes some of the
determinism patches even though the output isn't yet reproducible. The
reason for adding them is that this makes the expressions of the
different interpreters more similar.

- references to -dev packages are now also removed in the 3.6 package,
thereby reducing its closure size