FifoManager: Remove redundant PauseAndLock parameters

PauseAndLock was only called with do_lock=true, and the function only
used unpauseOnUnlock when do_lock was false.

Source/Core/Core/Core.cpp

@@ -784,7 +784,7 @@ static bool PauseAndLock(Core::System& system)
 
   // video has to come after CPU, because CPU thread can wait for video thread
   // (s_efbAccessRequested).
-  system.GetFifo().PauseAndLock(true, false);
+  system.GetFifo().PauseAndLock();
 
   ResetRumble();