Don't pass the AppHooks as pointer

It's not permitted to pass a nullptr to the `app_hooks_update`. So a
reference should be used.

CppCheck says one shouldn't take pointer to a temporary.

source/lib/app_hooks.cpp

@@ -76,11 +76,9 @@ static AppHooks default_ah = ah;
 // register the specified hook function pointers. any of them that
 // are non-zero override the previous function pointer value
 // (these default to the stub hooks which are functional but basic).
-void app_hooks_update(AppHooks* new_ah)
+void app_hooks_update(const AppHooks& new_ah)
 {
-	ENSURE(new_ah);
-
-#define OVERRIDE_IF_NONZERO(HOOKNAME) if(new_ah->HOOKNAME) ah.HOOKNAME = new_ah->HOOKNAME;
+#define OVERRIDE_IF_NONZERO(HOOKNAME) if(new_ah.HOOKNAME) ah.HOOKNAME = new_ah.HOOKNAME;
 	OVERRIDE_IF_NONZERO(get_log_dir)
 	OVERRIDE_IF_NONZERO(bundle_logs)
 	OVERRIDE_IF_NONZERO(display_error)

source/lib/app_hooks.h

@@ -153,7 +153,7 @@ struct AppHooks
  * override the previous function pointer value
  * (these default to the stub hooks which are functional but basic).
  **/
-void app_hooks_update(AppHooks* ah);
+void app_hooks_update(const AppHooks& ah);
 
 /**
  * was the app hook changed via app_hooks_update from its default value?

source/ps/GameSetup/GameSetup.cpp

@@ -208,12 +208,11 @@ void InitVfs(const CmdLineArgs& args)
 	psSetLogDir(logs);
 	// desired location for crashlog is now known. update AppHooks ASAP
 	// (particularly before the following error-prone operations):
-	AppHooks hooks{
+	app_hooks_update({
 		.get_log_dir = psLogDir,
 		.bundle_logs = psBundleLogs,
 		.display_error = psDisplayError
-	};
-	app_hooks_update(&hooks);
+	});
 
 	g_VFS = CreateVfs();