Make realtime scheduling less aggressive

On the Wine side. Instead of always having it enabled and disabling it
when it could potentially hurt (i.e. when handling GUI related things),
we'll now only enable it when it's potentially beneficial. This way we
don't have to constantly switch scheduling policies on the GUI thread.

src/wine-host/utils.cpp

@@ -86,10 +86,7 @@ MainContext::MainContext()
     // we'll run the timer on a 30 second interval.
     async_handle_watchdog_timer(5s);
 
-    watchdog_handler = Win32Thread([&]() {
-        set_realtime_priority(false);
-        watchdog_context.run();
-    });
+    watchdog_handler = Win32Thread([&]() { watchdog_context.run(); });
 }
 
 void MainContext::run() {