[clang] [clang] Check validity of SYCL device target (PR #172366)

[Tom Honermann via cfe-commits]

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@@ -286,11 +286,6 @@ consteval void bad25() {}
 [[clang::sycl_kernel_entry_point(BADKN<26>)]]
 [[noreturn]] void bad26();
 
-// expected-error at +3 {{attribute 'target' multiversioning cannot be combined with attribute 'clang::sycl_kernel_entry_point'}}
-__attribute__((target("avx"))) void bad27();
-[[clang::sycl_kernel_entry_point(BADKN<27>)]]
-__attribute__((target("sse4.2"))) void bad27();
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tahonermann wrote:

Can we preserve this test case for host compilation? We should be able to put it in a `#if !defined(__SYCL_DEVICE_ONLY__)` block.

https://github.com/llvm/llvm-project/pull/172366