ALSA: echoaudio: re-enable IRQs on failure path

This should be spin_unlock_irq() instead of spin_lock().

Fixes: 6c331254 ("ALSA: echoaudio: Prevent races in calls to set_audio_format()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200713105324.GB251988@mwandaSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/echoaudio/echoaudio.c

@@ -721,7 +721,7 @@ static int pcm_prepare(struct snd_pcm_substream *substream)
 	spin_lock_irq(&chip->lock);
 
 	if (snd_BUG_ON(!is_pipe_allocated(chip, pipe_index))) {
-		spin_unlock(&chip->lock);
+		spin_unlock_irq(&chip->lock);
 		return -EINVAL;
 	}