[clang] [OpenACC] Implement 'if' clause for Compute Constructs (PR #88411)

[Alexey Bataev via cfe-commits]

================
@@ -81,6 +100,51 @@ class OpenACCDefaultClause : public OpenACCClauseWithParams {
                                       SourceLocation EndLoc);
 };
 
+/// Represents one of the handful of classes that has an optional/required
+/// 'condition' expression as an argument.
+class OpenACCClauseWithCondition : public OpenACCClauseWithParams {
+  Expr *ConditionExpr;
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alexey-bataev wrote:

```suggestion
  Expr *ConditionExpr = nullptr;
```


https://github.com/llvm/llvm-project/pull/88411