[clang] [clang][NFC] sort C standards on status page in reverse chronological order (PR #102844)

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h-vetinari wrote:

CC @AaronBallman @cor3ntin, this PR will have painful conflicts whenever there are updates to the C status page. Happy to close if there's no interest, but is yes, perhaps you could take a look? :)

https://github.com/llvm/llvm-project/pull/102844