Revert "Add a wait for threads when we hand away control. Probably not needed due to all the extra processing during end-of-frame."

This reverts commit e1a4ef93b6.

apu/apu.cpp

@@ -758,16 +758,6 @@ static inline void S9xAPUUpdateClock (void)
     S9xAPUSetReferenceTime(CPU.Cycles);
 }
 
-void S9xAPUWait (void)
-{
-#ifdef USE_THREADS
-    if (spc::using_threads)
-    {
-        S9xAPUThreadWait();
-    }
-#endif
-}
-
 uint8 S9xAPUReadPort (int port)
 {
 #ifdef USE_THREADS

apu/apu.h

@@ -230,6 +230,5 @@ void S9xClearSamples (void);
 bool8 S9xMixSamples (uint8 *, int);
 void S9xSetSamplesAvailableCallback (apu_callback, void *);
 void S9xUpdateDynamicRate (int, int);
-void S9xAPUWait (void);
 
 #endif

cpuexec.cpp

@@ -319,12 +319,9 @@ void S9xMainLoop (void)
 	#ifdef DEBUGGER
 		if (!(CPU.Flags & FRAME_ADVANCE_FLAG))
 	#endif
-		S9xAPUWait();
 		S9xSyncSpeed();
 		CPU.Flags &= ~SCAN_KEYS_FLAG;
 	}
-
-
 }
 
 static inline void S9xReschedule (void)