[clang] [Clang] Allow raw string literals in C as an extension (PR #88265)

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Sirraide wrote:

> I don't think we should allow it for C++11 and later modes

To clarify, should we allow enabling them in e.g. `c++03` mode if `-fraw-string-literals` is passed? I don’t see why not, but I’m not entirely sure whether you’re saying we should not support that flag in C++ (neither the positive nor the negative variant) at all or just not in C++11 and later.

https://github.com/llvm/llvm-project/pull/88265