[clang] [OpenACC} Improve diagnostics for 'tag's on clauses/directives (PR #77957)

[Alexey Bataev via cfe-commits]

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@@ -164,6 +164,48 @@ bool isOpenACCSpecialToken(OpenACCSpecialTokenKind Kind, Token Tok) {
   llvm_unreachable("Unknown 'Kind' Passed");
 }
 
+// Used for cases where we have a token we want to check against an
+// 'identifier-like' token, but don't want to give awkward error messages in
+// cases where it is accidentially a keyword.
----------------
alexey-bataev wrote:

```suggestion
/// Used for cases where we have a token we want to check against an
/// 'identifier-like' token, but don't want to give awkward error messages in
/// cases where it is accidentially a keyword.
```

https://github.com/llvm/llvm-project/pull/77957