fix module-hygiene corner case by relying more on syntax objects

fix module-hygiene corner case by relying more on syntax objects

* module/ice-9/psyntax.scm (chi-macro): Instead of assuming that output
  of a macro should be scoped relative to the module that was current
  when the macro was defined, allow the module information associated
  with the syntax object itself to pass through unmolested. Fixes bug
  29860.
  (datum->syntax): Propagate the module of the identifier through to the
  new syntax object, so that datum->syntax preserves module hygiene in
  addition to lexical hygiene.
  (include, include-from-path): Refactor to plumb though the hygiene
  information from the filename instead of the `include', allowing
  hygiene from the original caller of include-from-path to propagate
  through.

* module/ice-9/psyntax-pp.scm: Regenerated.

* test-suite/tests/syncase.test ("macro-generating macro"): Add test for
  bug 29860.