Several verifier test checks not being run in HLSLFileCheck folder

[sudonatalie]

The test at tools/clang/test/HLSLFileCheck/hlsl/types/conversions/attributes_Mod.hlsl has many expected-warning, fxc-pass, fxc-warning and verify-ast comments, but I don't think any are being checked since the RUN line is just for FileCheck.

This is a follow up from #6196

[llvm-beanz]

Fun... There's actually a bunch of tests in the HLSLFileCheck directory that have verifier expected comments:

tools/clang/test/HLSLFileCheck/hlsl/compile_options/WX.hlsl tools/clang/test/HLSLFileCheck/hlsl/intrinsics/basic/intrinsic-examples_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/operators/binary/vector-matrix-binops.hlsl tools/clang/test/HLSLFileCheck/hlsl/template/dependent-sized_array.hlsl tools/clang/test/HLSLFileCheck/hlsl/template/elaborated-type-specifier.hlsl tools/clang/test/HLSLFileCheck/hlsl/template/templateTypename.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/attributes_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/const-expr_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/const-exprB_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/functions_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/implicit-casts_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/indexing-operator_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/literals_exact_precision_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/literals_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/packreg_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/scalar-assignments_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/string_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/template-checks_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/typemods-syntax_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/varmods-syntax_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/matrix/matrix-assignments_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/matrix/matrix-syntax_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/vector/vector-assignments_Mod.hlsl

We should inspect all of these because the legacy "FileChecker" infrastructure doesn't support verifier tests in that folder.

[pow2clk]

The vast majority of these were introduced with the first commit, when perhaps the idea was to have verifier support. The handful of exceptions may have been from careless copy-paste of existing clang testing. In several cases, the verifier comments are either meaningless or redundant with filecheck notations, there's a large class of tests where the only check is for main

Introduced by the first commit: tools/clang/test/HLSLFileCheck/hlsl/compile_options/WX.hlsl tools/clang/test/HLSLFileCheck/hlsl/intrinsics/basic/intrinsic-examples_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/template-checks_Mod.hlsl

More recent: tools/clang/test/HLSLFileCheck/hlsl/operators/binary/vector-matrix-binops.hlsl - this one came from commits circa-2018, but has CHECK equivalents

Copied from template tests tools/clang/test/HLSLFileCheck/hlsl/template/dependent-sized_array.hlsl - has an un-filechecked warning that isn't relevant to dxc. tools/clang/test/HLSLFileCheck/hlsl/template/elaborated-type-specifier.hlsl tools/clang/test/HLSLFileCheck/hlsl/template/templateTypename.hlsl

Introduced by first commit. Only CHECK is for @main tools/clang/test/HLSLFileCheck/hlsl/types/conversions/attributes_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/const-expr_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/const-exprB_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/functions_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/implicit-casts_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/indexing-operator_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/literals_exact_precision_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/literals_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/packreg_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/scalar-assignments_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/string_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/typemods-syntax_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/conversions/varmods-syntax_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/matrix/matrix-assignments_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/matrix/matrix-syntax_Mod.hlsl tools/clang/test/HLSLFileCheck/hlsl/types/vector/vector-assignments_Mod.hlsl