Core: pass down Core::System reference to all services (#4272)

* Core: pass down Core::System reference to all services

This has to be done at once due to unified interface used by HLE/LLE switcher

* apt: eliminate Core::System::GetInstance

* gpu_gsp: eliminate Core::System::GetInstance in service

* hid: eliminate Core::System::GetInstance

* nwm: eliminate Core::System::GetInstance

* err_f: eliminate Core::System::GetInstance

src/core/hle/service/cfg/cfg.h

@@ -15,6 +15,10 @@ namespace FileSys {
 class ArchiveBackend;
 }
 
+namespace Core {
+class System;
+}
+
 namespace Service::CFG {
 
 enum SystemModel {
@@ -407,7 +411,7 @@ private:
     u32 preferred_region_code = 0;
 };
 
-void InstallInterfaces(SM::ServiceManager& service_manager);
+void InstallInterfaces(Core::System& system);
 std::shared_ptr<Module> GetCurrentModule();
 
 } // namespace Service::CFG