[clang] [C11] Implement WG14 N1285 (temporary lifetimes) (PR #133472)

[Aaron Ballman via cfe-commits]

AaronBallman wrote:

> Looks like this breaks tests on macOS: http://45.33.8.238/macm1/104220/step_6.txt
> 
> Please take a look and revert for now if it takes a while to fix.

This should already be addressed by 5a1b4ec6f4b773f191e98183ae4628785729daa1, I'm watching the bots to make sure they go back to green.

https://github.com/llvm/llvm-project/pull/133472