8163305: Add some print instrumentation to java/nio/channels/Selector/RacyDeregister
Summary: Perform more iterations on Windows, and on all platforms if the test enters the failure branch, poll for an extra period of time to determine whether it might have succeeded with a longer timeout
Reviewed-by: chegar

6429204: (se) Concurrent Selector.register and SelectionKey.interestOps can ignore interestOps
Reviewed-by: alanb