[compiler-rt] [compiler-rt][XRay] Make `xray_interface.h` C compliant (PR #140068)

[A. Jiang via llvm-commits]

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@@ -1,21 +1,21 @@
 // Check that we can patch and un-patch on demand, and that logging gets invoked
 // appropriately.
 //
-// RUN: %clangxx_xray -fxray-instrument -std=c++11 %s -o %t
+// RUN: %clang_xray -fxray-instrument -std=c23 %s -o %t
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frederick-vs-ja wrote:

I think there should be both `.c` and `.cpp` test files.

https://github.com/llvm/llvm-project/pull/140068