htc: implement mux side of connecting (and more)

libraries/libstratosphere/source/htclow/driver/htclow_driver_manager.hpp

@@ -33,11 +33,14 @@ namespace ams::htclow::driver {
             DriverManager() = default;
 
             Result OpenDriver(impl::DriverType driver_type);
+            void CloseDriver();
 
             impl::DriverType GetDriverType();
 
             IDriver *GetCurrentDriver();
 
+            void Cancel();
+
             void SetDebugDriver(IDriver *driver);
     };