[llvm] [X86] Remove tests for non-existant intrinsics. NFC (PR #196237)

[Phoebe Wang via llvm-commits]

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@@ -514,4 +372,8 @@ declare <2 x i64> @llvm.x86.sse2.psrai.q(<2 x i64>, i32) ; does not exist
 ;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
 ; CHECK: {{.*}}
 ; X64: {{.*}}
+; X64-AVX2: {{.*}}
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phoebewang wrote:

Maybe remove such prefixes?

https://github.com/llvm/llvm-project/pull/196237