[llvm] fix template compilation issue in flang-rt, fix issue #160534 (PR #161250)

[Valentin Clement バレンタイン クレメン via llvm-commits]

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@@ -340,8 +340,8 @@ struct MatmulTransposeHelper {
     RUNTIME_CHECK(terminator, xCatKind.has_value() && yCatKind.has_value());
     RUNTIME_CHECK(terminator, xCatKind->first == XCAT);
     RUNTIME_CHECK(terminator, yCatKind->first == YCAT);
-    if constexpr (constexpr ResultTy resultType{
-                      GetResultType(XCAT, XKIND, YCAT, YKIND)}) {
+    constexpr ResultTy resultType{GetResultType(XCAT, XKIND, YCAT, YKIND)};
+    if constexpr (resultType) {
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clementval wrote:

This might be ok to change. 

https://github.com/llvm/llvm-project/pull/161250