[clang] [HLSL] make semantic matching case insensitive (PR #129773)

[Chris B via cfe-commits]

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@@ -4790,7 +4790,7 @@ def HLSLPackOffset: HLSLAnnotationAttr {
 }
 
 def HLSLSV_DispatchThreadID: HLSLAnnotationAttr {
-  let Spellings = [HLSLAnnotation<"SV_DispatchThreadID">];
+  let Spellings = [HLSLAnnotation<"sv_dispatchthreadid">];
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llvm-beanz wrote:

Can we add a check in the tablegen code to error if the HLSLAnnotation attributes ever have a spelling with a capital letter?

I just don't want us to screw this up accidentally and break some new attribute.

https://github.com/llvm/llvm-project/pull/129773