[clang] [Clang] add option --offload-jobs=N (PR #135229)

[Joseph Huber via cfe-commits]

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@@ -57,6 +57,7 @@
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Process.h"
+#include "llvm/Support/ThreadPool.h"
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jhuber6 wrote:

```suggestion
```
Unused now?

https://github.com/llvm/llvm-project/pull/135229