Fix a schedule event assert on ClearCacheThreadSafe

I didn't know that telling that you don't schedule from the CPU thread prevents an assert because it by default assumes you use the CPU thread, but in the case of ClearCacheThreadSafe, it's used from the GUI thread.

Source/Core/Core/PowerPC/JitCommon/JitCache.cpp

@@ -84,7 +84,7 @@ void JitBaseBlockCache::Clear()
 
 void JitBaseBlockCache::SchedulateClearCacheThreadSafe()
 {
-  CoreTiming::ScheduleEvent(0, s_clear_jit_cache_thread_safe);
+  CoreTiming::ScheduleEvent(0, s_clear_jit_cache_thread_safe, 0, CoreTiming::FromThread::NON_CPU);
 }
 
 void JitBaseBlockCache::Reset()