[clang] [clang][SME] Emit error for OpenMP captured regions in SME functions (PR #124590)

[Benjamin Maxwell via cfe-commits]

================
@@ -4568,9 +4568,28 @@ buildCapturedStmtCaptureList(Sema &S, CapturedRegionScopeInfo *RSI,
   return false;
 }
 
+static std::optional<int>
+isOpenMPCapturedRegionInArmSMEFunction(Sema const &S, CapturedRegionKind Kind) {
+  if (!S.getLangOpts().OpenMP || Kind != CR_OpenMP)
+    return false;
+  FunctionDecl *FD = S.getCurFunctionDecl(/*AllowLambda=*/true);
+  if (!FD)
+    return false;
----------------
MacDue wrote:

```suggestion
  if (!S.getLangOpts().OpenMP || Kind != CR_OpenMP)
    return {};
  FunctionDecl *FD = S.getCurFunctionDecl(/*AllowLambda=*/true);
  if (!FD)
    return {};
```

https://github.com/llvm/llvm-project/pull/124590