[clang] [Clang][P1061] Add stuctured binding packs (PR #121417)

[via cfe-commits]

cor3ntin wrote:

> > Does this mean we should adjust the cxx_status page to not say Clang 20? I also see there is a conflict with the ReleaseNotes.md where it appears all of the C++2c items no longer exist. (I guess that is because it is for the next release.)
> 
> Meh, let's assume 20 and we can edit it later if we end up not merging, I think. And yes, the release notes have been reset for 21, I guess you can remove the entry entirely to make it easier to cherry-pick to 20

Edit: On second thought, lets revert cxx_status.html too to avoid confusion

https://github.com/llvm/llvm-project/pull/121417