Revert "win-asio: clear thread on exit"

This would clear the global thread when multiple devices are used.
This reverts commit 76149b0.

Author: pkviet

src/asio-input.cpp

@@ -310,8 +310,6 @@ class AudioCB : public juce::AudioIODeviceCallback {
 
 	~AudioCB()
 	{
-		if (_thread)
-			_thread->stopThread(200);
 		bfree(_name);
 	}