cpu/cpu - Add way to signal interrupt from outside

cpu/cpu.cpp

@@ -103,6 +103,11 @@ void Cpu::doRet()
   state.PC = popStack16();
 }
 
+void Cpu::signalInterrupt(InterruptType it)
+{
+  state.IF |= it;
+}
+
 bool Cpu::decodeCond(u8 cc)
 {
   switch(cc)

cpu/cpu.h

@@ -132,9 +132,7 @@ public:
   unsigned long processed_mcycles;
 
 
-  void signal(InterruptType it);
+  void signalInterrupt(InterruptType it);
-  void setIE(u8 val);
-  u8 getIE();
 
   void step();
 };