VITA: fix audio playback

(cherry picked from commit 1dbb813316)

src/audio/vita/SDL_vitaaudio.c

@@ -130,7 +130,8 @@ static bool VITAAUD_OpenDevice(SDL_AudioDevice *device)
 
 static bool VITAAUD_PlayDevice(SDL_AudioDevice *device, const Uint8 *buffer, int buffer_size)
 {
-    return (sceAudioOutOutput(device->hidden->port, buffer) == 0);
+    // sceAudioOutOutput returns amount of samples queued or < 0 on error
+    return (sceAudioOutOutput(device->hidden->port, buffer) >= 0);
 }
 
 // This function waits until it is possible to write a full sound buffer