Fix warnings

This fixes warnings in:
- Source/Core/InputCommon/ControllerEmu.h: avoid shadowing other
  variables (my fault)
- Source/Core/Core/IPC_HLE/WII_IPC_HLE.h: made
  SDIO_EventNotify_CPUThread static as it's not used anywhere else

Source/Core/Core/IPC_HLE/WII_IPC_HLE.cpp

@@ -100,7 +100,7 @@ static void EnqueueEvent(u64 userdata, s64 cycles_late = 0)
   Update();
 }
 
-void SDIO_EventNotify_CPUThread(u64 userdata, s64 cycles_late)
+static void SDIO_EventNotify_CPUThread(u64 userdata, s64 cycles_late)
 {
   auto device =
       static_cast<CWII_IPC_HLE_Device_sdio_slot0*>(GetDeviceByName("/dev/sdio/slot0").get());