[clang] [llvm] [Clang][OpenMP] Implement Loop splitting `#pragma omp split` directive (PR #183261)

[Michael Kruse via cfe-commits]

================
@@ -1023,6 +1023,93 @@ class OMPSizesClause final
   }
 };
 
+/// This represents the 'counts' clause in the '#pragma omp split' directive.
+///
+/// \code
+/// #pragma omp split counts(3, 5, 2)
----------------
Meinersbur wrote:

```suggestion
/// #pragma omp split counts(3, 5, omp_fill, 2)
```
`omp_fill` is mandatory

https://github.com/llvm/llvm-project/pull/183261