This brings back the package PkgChdrUtils after it was removed in
d9f8c08. Its contents were moved because most of the contents were
synthesizable, but many existing testbenches might still reference the
old package name. This new version of PkgChdrUtils simply imports then
exports the things it used to include. New testbenches are encouraged
to reference the new files instead of PkgChdrUtils.
Original-commit: 7992198889c172db04dd324bac42819c51d6ee79