[clang] [clang][Sema] Split SYCLKernel back into its own attribute (PR #162868)

[Tom Honermann via cfe-commits]

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@@ -1599,8 +1599,15 @@ def CUDAShared : InheritableAttr {
 }
 def : MutualExclusions<[CUDAConstant, CUDAShared, HIPManaged]>;
 
+def SYCLKernel : InheritableAttr {
+  let Spellings = [Clang<"sycl_kernel">];
+  let Subjects = SubjectList<[FunctionTmpl]>;
+  let LangOpts = [SYCLDevice];
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tahonermann wrote:

Please don't assume that what makes sense for `__global__`, `__kernel`, etc... makes sense for `sycl_kernel`. The goal for this PR should be to put `sycl_kernel` back the way it was before https://github.com/llvm/llvm-project/pull/137882. Don't try to improve it.

https://github.com/llvm/llvm-project/pull/162868