message: Pass --target down to rustdoc if specified with host target
diff: @@ -200,11 +200,12 @@ fn run_doc_tests(
  p.arg(unit.target.src_path().path().unwrap());
  }
  - if doctest_xcompile {
  if let CompileKind::Target(target) = unit.kind {
  // use `rustc_target()` to properly handle JSON target paths
  p.arg("--target").arg(target.rustc_target());
  }
  +
  + if doctest_xcompile {
  p.arg("-Zunstable-options");
  p.arg("--enable-per-target-ignores");
  if let Some((runtool, runtool_args)) = compilation.target_runner(unit.kind) {
  