GCAdapter: Report libusb open errors to the user

If opening the adapter fails, report the libusb error message in the GUI
instead of “No Adapter Detected”.

The error condition is removed when the adapter is unplugged.

Source/Core/Core/Analytics.cpp

@@ -391,9 +391,9 @@ void DolphinAnalytics::MakePerGameBuilder()
   // We grab enough to tell what percentage of our users are playing with keyboard/mouse, some kind
   // of gamepad
   // or the official gamecube adapter.
-  builder.AddData("gcadapter-detected", GCAdapter::IsDetected());
+  builder.AddData("gcadapter-detected", GCAdapter::IsDetected(nullptr));
   builder.AddData("has-controller", Pad::GetConfig()->IsControllerControlledByGamepadDevice(0) ||
-                                        GCAdapter::IsDetected());
+                                        GCAdapter::IsDetected(nullptr));
 
   m_per_game_builder = builder;
 }