[llvm] [llvm][AArch64] Drop unused&redundant field in the TargetParserTest. NFC (PR #97367)

[Jon Roelofs via llvm-commits]

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@@ -1071,10 +1071,29 @@ TEST(TargetParserTest, ARMPrintSupportedExtensions) {
   EXPECT_EQ(std::string::npos, captured.find("xscale"));
 }
 
-class AArch64CPUTestFixture : public ::testing::TestWithParam<
-                                  ARMCPUTestParams<AArch64::ExtensionBitset>> {
+template <typename T> struct AArch64CPUTestParams : public ARMCPUTestParams<T> {
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jroelofs wrote:

good point

https://github.com/llvm/llvm-project/pull/97367