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@mwanda
Signed-off-by: Takashi Iwai <tiwai@suse.de>