yuzu_cmd/config: Silent implicit cast warning

src/yuzu_cmd/config.cpp

@@ -366,7 +366,7 @@ void Config::ReadValues() {
     Settings::values.enable_audio_stretching =
         sdl2_config->GetBoolean("Audio", "enable_audio_stretching", true);
     Settings::values.audio_device_id = sdl2_config->Get("Audio", "output_device", "auto");
-    Settings::values.volume = sdl2_config->GetReal("Audio", "volume", 1);
+    Settings::values.volume = static_cast<float>(sdl2_config->GetReal("Audio", "volume", 1));
 
     Settings::values.language_index = sdl2_config->GetInteger("System", "language_index", 1);