[clang] [HLSL] Add matrix constructors using initalizer lists (PR #162743)

[Farzon Lotfi via cfe-commits]

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@@ -1877,6 +1887,93 @@ void InitListChecker::CheckReferenceType(const InitializedEntity &Entity,
     AggrDeductionCandidateParamTypes->push_back(DeclType);
 }
 
+void InitListChecker::CheckMatrixType(const InitializedEntity &Entity,
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farzonl wrote:

@llvm-beanz the `initializer list` work simplifies but does not make us remove `CheckMatrixType`. It simplifies it so that all we have to do is support the scalar case by looping over the number of inits and calling `CheckSubElementType`. So I deleted all the vector and matrix type handeling

https://github.com/llvm/llvm-project/pull/162743