Qt: Support SDL audio backend

src/duckstation-qt/qthostinterface.cpp

@@ -8,6 +8,7 @@
 #include "core/game_list.h"
 #include "core/gpu.h"
 #include "core/system.h"
+#include "frontend-common/sdl_audio_stream.h"
 #include "frontend-common/sdl_controller_interface.h"
 #include "qtsettingsinterface.h"
 #include "qtutils.h"
@@ -275,6 +276,9 @@ std::unique_ptr<AudioStream> QtHostInterface::CreateAudioStream(AudioBackend bac
     case AudioBackend::Cubeb:
       return AudioStream::CreateCubebAudioStream();
 
+    case AudioBackend::SDL:
+      return SDLAudioStream::Create();
+
     default:
       return nullptr;
   }