Removing useless func IsAlive, since it's handled by ISetAllocated

mesosphere/source/interrupts/KInterruptEvent.cpp

@@ -13,13 +13,7 @@ Result KInterruptEvent::Initialize(int irqId, u32 flags)
     // TODO implement
     (void)flags;
     this->irqId = irqId;
-    isInitialized = true;
     return ResultSuccess();
 }
 
-bool KInterruptEvent::IsAlive() const
-{
-    return isInitialized;
-}
-
 }