SI_Device: Provide proper insertion/extraction operators for SIDevices enum

Allows the enumeration to be safely used with our type parsing
functions.

Source/Core/Core/ConfigManager.cpp

@@ -500,7 +500,7 @@ void SConfig::LoadCoreSettings(IniFile& ini)
   core->Get("BBA_MAC", &m_bba_mac);
   for (size_t i = 0; i < std::size(m_SIDevice); ++i)
   {
-    core->Get(fmt::format("SIDevice{}", i), (u32*)&m_SIDevice[i],
+    core->Get(fmt::format("SIDevice{}", i), &m_SIDevice[i],
               (i == 0) ? SerialInterface::SIDEVICE_GC_CONTROLLER : SerialInterface::SIDEVICE_NONE);
     core->Get(fmt::format("AdapterRumble{}", i), &m_AdapterRumble[i], true);
     core->Get(fmt::format("SimulateKonga{}", i), &m_AdapterKonga[i], false);

Source/Core/Core/HW/SI/SI_Device.cpp

@@ -4,8 +4,11 @@
 
 #include "Core/HW/SI/SI_Device.h"
 
+#include <istream>
 #include <memory>
+#include <ostream>
 #include <string>
+#include <type_traits>
 
 #include <fmt/format.h>
 
@@ -21,6 +24,28 @@
 
 namespace SerialInterface
 {
+std::ostream& operator<<(std::ostream& stream, SIDevices device)
+{
+  stream << static_cast<std::underlying_type_t<SIDevices>>(device);
+  return stream;
+}
+
+std::istream& operator>>(std::istream& stream, SIDevices& device)
+{
+  std::underlying_type_t<SIDevices> value;
+
+  if (stream >> value)
+  {
+    device = static_cast<SIDevices>(value);
+  }
+  else
+  {
+    device = SIDevices::SIDEVICE_NONE;
+  }
+
+  return stream;
+}
+
 ISIDevice::ISIDevice(SIDevices device_type, int device_number)
     : m_device_number(device_number), m_device_type(device_type)
 {

Source/Core/Core/HW/SI/SI_Device.h

@@ -4,6 +4,7 @@
 
 #pragma once
 
+#include <iosfwd>
 #include <memory>
 #include "Common/CommonTypes.h"
 
@@ -63,6 +64,9 @@ enum SIDevices : int
   SIDEVICE_COUNT,
 };
 
+std::ostream& operator<<(std::ostream& stream, SIDevices device);
+std::istream& operator>>(std::istream& stream, SIDevices& device);
+
 class ISIDevice
 {
 public: