[clang] [clang] Fix preprocessor output from #embed (PR #126742)

[via cfe-commits]

llvmbot wrote:

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Failed to cherry-pick: 3be48a6f809afccc9bcddc8cf94492812b49e1f7

https://github.com/llvm/llvm-project/actions/runs/13326798464

Please manually backport the fix and push it to your github fork.  Once this is done, please create a [pull request](https://github.com/llvm/llvm-project/compare)

https://github.com/llvm/llvm-project/pull/126742