QWinEventNotifiers were limited to 62 instances, because of
WaitForMultipleObject's limitation to MAXIMUM_WAIT_OBJECTS - 1 handles.
Use the RegisterWaitForSingleObject API which does not have this
restriction and executes waits in threads managed by the system. A
central manual reset event per event dispatcher is signaled in the
RegisterWaitForSingleObject callback and waited for in the event loop.
[ChangeLog][QtCore][QWinEventNotifier] QWinEventNotifier is not
restricted to 62 instances anymore.
Task-number: QTBUG-8819
Change-Id: I2c749951453a4b699cc50dada0d6017440b67a4a
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>
5c6210e345