[llvm] [libsycl][NFC] Suppress shadow warnings from LLVM headers (PR #225089)

[Kseniya Tikhomirova via llvm-commits]

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@@ -17,9 +17,13 @@
 
 #include <sycl/__impl/detail/config.hpp>
 
+// Suppress some additional warnings enabled in libsycl for LLVM headers.
+#pragma GCC diagnostic push
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KseniyaTikhomirova wrote:

can we have a macro for this? useful to update, reuse and grep

https://github.com/llvm/llvm-project/pull/225089