Add NR O-RU (#211)
This is a PR that will add a functional vrtsim-based nr-oru to the build
system. This is only slightly different SW to the one being presented at
the OAI summer 2026 workshop.
Reviewed-by: Robert Schmidt <robert.schmidt@openairinterface.org>
Reviewed-By: Merkebu Girmay <merkebu.girmay@openairinterface.org>