Make EXI use CoreTiming events like everything else instead of having its own slow special check.

Microphone is probably wrong/mistimed because it doesn't take into
account cycles late, but that's not a new issue here.

Source/Core/Core/PowerPC/PowerPC.cpp

@@ -303,10 +303,6 @@ void UpdatePerformanceMonitor(u32 cycles, u32 num_load_stores, u32 num_fp_inst)
 
 void CheckExceptions()
 {
-	// Make sure we are checking against the latest EXI status. This is required
-	// for devices which interrupt frequently, such as the gc mic
-	ExpansionInterface::UpdateInterrupts();
-
 	// Read volatile data once
 	u32 exceptions = ppcState.Exceptions;