[clang] [llvm] [DirectX] Add isinf f16 emulation for SM6.8 and lower (PR #156932)

[Farzon Lotfi via llvm-commits]

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@@ -180,7 +180,8 @@ class Triple {
     DXILSubArch_v1_6,
     DXILSubArch_v1_7,
     DXILSubArch_v1_8,
-    LatestDXILSubArch = DXILSubArch_v1_8,
+    DXILSubArch_v1_9,
+    LatestDXILSubArch = DXILSubArch_v1_9,
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farzonl wrote:

`LatestDXILSubArch` must always match the latest dxil version. i believe its uses for the `6.x` target triple format.

https://github.com/llvm/llvm-project/pull/156932