[clang] [flang] [llvm] [openmp] [OpenMP][Offload] Add offload runtime support for dyn_groupprivate clause (PR #152831)

[Kevin Sala Penades via llvm-commits]

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@@ -267,10 +267,22 @@ struct __tgt_target_non_contig {
 extern "C" {
 #endif
 
+/// The OpenMP access group type. The criterion for grupping tasks using a
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kevinsala wrote:

That description is taken from the OpenMP spec:

```
access group type:
  A criterion for grouping tasks using a specific grouping property. Each group of tasks
  classified under that criterion is called an access group. All tasks in an access group have the
  same value for the grouping property of the access group type. The access group type
  indicates the scope and access properties of groupprivate variables and dynamic groupprivate
  blocks in constructs, directives and routines. A task can belong to at most one access group
  for the same access group type.
```

https://github.com/llvm/llvm-project/pull/152831