Add `-print-resource-dir` to pnacl-clang.

Done in the fashion of https://reviews.llvm.org/D31447.

This is required to be able to effectivelly use clang-scan-deps with pnacl-clang.

Change-Id: Id82a117c89fe1729eaf87bb8f921fbc4442984fc
Reviewed-on: https://chromium-review.googlesource.com/c/native_client/pnacl-clang/+/2674739
Reviewed-by: Kousik Kumar <kousikk@google.com>
Reviewed-by: Derek Schuff <dschuff@chromium.org>

• include/clang/Driver/Options.td[diff]
• lib/Driver/Driver.cpp[diff]
• test/Driver/immediate-options.c[diff]