[clang] [HLSL] Add matrix support to atan2 (PR #194984)

[Deric C. via cfe-commits]

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@@ -11,3 +11,9 @@ double2 test_vec_double_builtin(double2 p0, double2 p1) {
     return TEST_FUNC(p0, p1);
   // expected-error at -1 {{1st argument must be a scalar or vector of 16 or 32 bit floating-point types (was 'double2' (aka 'vector<double, 2>'))}}
 }
+
+// Temporary matrix workarround until we have proper matrix support in the builtins.
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Icohedron wrote:

nit
```suggestion
// Temporary matrix workaround until we have proper matrix support in the builtins.
```

https://github.com/llvm/llvm-project/pull/194984