Nerf OSX warning about use of this in lambda.

indra/newview/llfloatereditextdaycycle.cpp

@@ -703,6 +703,7 @@ void LLFloaterEditExtDayCycle::checkAndConfirmSettingsLoss(on_confirm_fn cb)
         LLNotificationsUtil::add("SettingsConfirmLoss", args, LLSD(),
             [this, cb](const LLSD&notif, const LLSD&resp)
             {
+                (void)this;
                 S32 opt = LLNotificationsUtil::getSelectedOption(notif, resp);
                 if (opt == 0)
                     cb();