[clang] [Clang][NFC] Remove incorrect SYCL tests (PR #109182)

[Alex Voicu via cfe-commits]

AlexVlx wrote:

Instead of removing the test case altogether,  does it not suffice to remove the SYCL reference / SYCL specific flag, which I interpret as the problem being addressed? SYCL per se is not a target, but rather a language? Apologies if I'm missing something.

https://github.com/llvm/llvm-project/pull/109182