[llvm] [libsycl] Generic code cleanup (PR #224330)

[Alexey Bader via llvm-commits]

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@@ -0,0 +1,20 @@
+// REQUIRES: any-device
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bader wrote:

Add LLVM license header to align with e0a2355cb95fe055372fdb59abc7257e6c0bb969.

https://github.com/llvm/llvm-project/pull/224330