IPC refactor part 1: Use explicit separate threads to process requests (#1447)

* Changes to allow explicit management of service threads

* Remove now unused code

* Remove ThreadCounter, its no longer needed

* Allow and use separate server per service, also fix exit issues

* New policy change: PTC version now uses PR number

Ryujinx.HLE/HOS/Services/Nv/INvDrvServices.cs

@@ -45,7 +45,7 @@ namespace Ryujinx.HLE.HOS.Services.Nv
 
         private bool _transferMemInitialized = false;
 
-        public INvDrvServices(ServiceCtx context)
+        public INvDrvServices(ServiceCtx context) : base(new ServerBase("NvservicesServer"))
         {
             _owner = null;
         }