Rollup merge of #150269 - update-nvptx-maintainers, r=jieyouxu

Remove inactive nvptx maintainer

Since I just saw the discussion in [#t-compiler > Starting to enforce Tier 2-to-3 downgrade](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/Starting.20to.20enforce.20Tier.202-to-3.20downgrade/with/564788312), and I saw him pinged on PRs or issues. His last active open-source contributions were in early 2022: https://github.com/RDambrosio016 and IIRC he also mentioned that he had moved on.

ping @RDambrosio016 so you can confirm or correct me, if you want to chime in. I also pinged him on Zulip.

cc @kjetilkjeka who is the other maintainer and active on related issues/prs for his target.

I'd leave it open for a while, but
r? @jieyouxu

Author: matthiaskrgr