Reset the device before closing it - fixes a hang with some audio drivers

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%40249

src/audio/dsp/SDL_dspaudio.c

@@ -233,6 +233,8 @@ static void DSP_CloseAudio(_THIS)
 		mixbuf = NULL;
 	}
 	if ( audio_fd >= 0 ) {
+		int value;
+		ioctl(audio_fd, SNDCTL_DSP_RESET, &value);
 		close(audio_fd);
 		audio_fd = -1;
 	}