Core: Fix first event scheduling after loading savestate

CHANGES

@@ -1,5 +1,6 @@
 0.10.0: (Future)
 Emulation fixes:
+ - Core: Fix first event scheduling after loading savestate
  - GBA Memory: Fix loading Thumb savestates when in ARM mode
 
 0.9.0: (2021-03-28)

src/core/timing.c

@@ -100,7 +100,10 @@ int32_t mTimingTick(struct mTiming* timing, int32_t cycles) {
 	if (timing->reroot) {
 		timing->root = timing->reroot;
 		timing->reroot = NULL;
-		*timing->nextEvent = mTimingNextEvent(timing); 
+		*timing->nextEvent = mTimingNextEvent(timing);
+		if (*timing->nextEvent <= 0) {
+			return mTimingTick(timing, 0);
+		}
 	}
 	return *timing->nextEvent;
 }