clang-cl: Add support for C23

Yonggang Luorequested to merge
lygstate/cmake:c23-clang-msvc into master

Although there is no cl -std:c23 flag, the underlying Clang compiler does have a C23 mode we can activate by passing -std=c23 through a clang-cl wrapper flag.

Also port the fix from !10082 (merged).

Fixes: #27038 (closed)
Signed-off-by: @lygstate
Backport: release
Topic-rename: clang-cl-c23

Edited by Brad King

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