Windows: Fixed duplicate call startAsyncRead() when installed SkipPolicy
Windows: Fixed duplicate call startAsyncRead() when installed SkipPolicy

Previously, when the established policy SkipPolicy, twice method is called startAsyncRead(), it can lead to undefined I/O behavior.

Now, the method startAsyncRead() is called only from the ReadOverlappedCompletionNotifier.

Change-Id: I9d615ac56eba6fff913d3028470bf037a3d825e2
Reviewed-by: Sergey Belyashov <8871b4c2d635fca691211507eadbac3d0bc2695a@gmail.com>
Reviewed-by: Thiago Augusto Correa <928c11138a15adc3fd64c3f8e36b851fee061ca7@gmail.com>
Reviewed-by: Denis Shienkov <6a9c747bd2ba446682324cf340d3b86f30cf4d55@gmail.com>

RoadWorksSoftware/QtSerialPort-OS2,RoadWorksSoftware/QtSerialPort-OS2,kobolabs/qtserialport,kobolabs/qtserialport