SDL.Audio: Fix openAudioDevice Changeable check (#229)

`foldChangeable` expects the value for Mandate as its first argument and
the value for Desire as its second, but `changes` in `openAudioDevice`
had them reversed. Swap them.

Author: spinnylights

src/SDL/Audio.hs

@@ -175,9 +175,9 @@ openAudioDevice OpenDeviceSpec{..} = liftIO $
         return (audioDevice, spec)
 
   where
-  changes = foldl (.|.) 0 [ foldChangeable (const Raw.SDL_AUDIO_ALLOW_FREQUENCY_CHANGE) (const 0) openDeviceFreq
-                          , foldChangeable (const Raw.SDL_AUDIO_ALLOW_FORMAT_CHANGE) (const 0) openDeviceFormat
-                          , foldChangeable (const Raw.SDL_AUDIO_ALLOW_CHANNELS_CHANGE) (const 0) openDeviceChannels
+  changes = foldl (.|.) 0 [ foldChangeable (const 0) (const Raw.SDL_AUDIO_ALLOW_FREQUENCY_CHANGE) openDeviceFreq
+                          , foldChangeable (const 0) (const Raw.SDL_AUDIO_ALLOW_FORMAT_CHANGE) openDeviceFormat
+                          , foldChangeable (const 0) (const Raw.SDL_AUDIO_ALLOW_CHANNELS_CHANGE) openDeviceChannels
                           ]
 
   channelsToWord8 Mono = 1