Windows: qabstractsocketengine.cpp: Fix -unity-build

Avoid the <windows.h> and <winsock2.h> conflict by excluding the file from unity build.

Task-number: QTBUG-135134
Change-Id: I34393856242ea67a30553b26a465e12d5f738cf5
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

src/network/CMakeLists.txt

@@ -406,6 +406,7 @@ qt_internal_extend_target(Network CONDITION WIN32
         kernel/qnetworkinterface_win.cpp
         kernel/qnetworkproxy_win.cpp
         socket/qabstractsocket.cpp
+        socket/qabstractsocketengine.cpp
         socket/qlocalserver.cpp
         socket/qlocalserver_win.cpp
         socket/qlocalsocket_win.cpp