FifoManager: Extract RestoreState from PauseAndLock

Replace calls of FifoManager::PauseAndLock(do_lock=false) with new
function RestoreState for clarity.

Source/Core/VideoCommon/VideoConfig.cpp

@@ -70,7 +70,7 @@ void VideoConfig::Refresh()
       g_Config.VerifyValidity();
 
       if (lock_gpu_thread)
-        system.GetFifo().PauseAndLock(false, true);
+        system.GetFifo().RestoreState(true);
     };
 
     s_config_changed_callback_id =