Compensate when Pinned

[emoryzheng(郑淼)]

Hello,
We have a test case about Loom, it can pass before;
The test case can be seen on attach file;

But it cannot pass after this patch:
```
commit de90a43c7a5f0b28bd0af9271de210475808ca0c
Author: Alan Bateman <alan.bateman at oracle.com>
Date:   Wed Sep 1 09:22:23 2021 +0100

    Replace lock/condition objects to simplify pinned park
```

Actually, this modify cause the test fail, because getCondition.await() will call tryCompensate() of ForkJoinPool eventually:
+    private void parkOnCarrierThread(long nanos) {
···
-                if (!parkPermit) {
-                    // wait to be signalled or interrupted
-                    getCondition().await();
···
+            if (!parkPermit) {
+                U.park(false, nanos);
             }

If there are 4 ForkJoinWorkerThread, and they are all pinned, how to make vt work correct?

Thanks，

Miao