Use latest resolution value for resolution hotkey OSD

Because CPU thread config changed callbacks are no longer instant,
g_Config.iEFBScale doesn't yet contain the new value when the hotkey OSD
code tries to read it.

Should fix https://bugs.dolphin-emu.org/issues/13343.

Source/Core/DolphinQt/HotkeyScheduler.cpp

@@ -359,8 +359,8 @@ void HotkeyScheduler::Run()
 
       // Graphics
       const auto efb_scale = Config::Get(Config::GFX_EFB_SCALE);
-      auto ShowEFBScale = []() {
-        switch (Config::Get(Config::GFX_EFB_SCALE))
+      const auto ShowEFBScale = [](int new_efb_scale) {
+        switch (new_efb_scale)
         {
         case EFB_SCALE_AUTO_INTEGRAL:
           OSD::AddMessage("Internal Resolution: Auto (integral)");
@@ -369,22 +369,22 @@ void HotkeyScheduler::Run()
           OSD::AddMessage("Internal Resolution: Native");
           break;
         default:
-          OSD::AddMessage(fmt::format("Internal Resolution: {}x", g_Config.iEFBScale));
+          OSD::AddMessage(fmt::format("Internal Resolution: {}x", new_efb_scale));
           break;
         }
       };
 
       if (IsHotkey(HK_INCREASE_IR))
       {
         Config::SetCurrent(Config::GFX_EFB_SCALE, efb_scale + 1);
-        ShowEFBScale();
+        ShowEFBScale(efb_scale + 1);
       }
       if (IsHotkey(HK_DECREASE_IR))
       {
         if (efb_scale > EFB_SCALE_AUTO_INTEGRAL)
         {
           Config::SetCurrent(Config::GFX_EFB_SCALE, efb_scale - 1);
-          ShowEFBScale();
+          ShowEFBScale(efb_scale - 1);
         }
       }