[clang] [Clang][SYCL] Introduce clang-sycl-linker to link SYCL offloading device code (Part 1 of many) (PR #112245)

[Alexey Bader via cfe-commits]

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@@ -0,0 +1,42 @@
+// Tests the clang-sycl-linker tool.
+//
+// Test a simple case without arguments.
+// RUN: %clangxx -fsycl -emit-llvm -c %s -o %t.bc
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bader wrote:

```suggestion
// RUN: %clangxx -emit-llvm -c %s -o %t.bc
```
`-fsycl` is useless here. We just need to create a file with LLVM magic number to make this test work.

https://github.com/llvm/llvm-project/pull/112245