ASoC: SOF: Intel: hda-dai: fix potential locking issue

The initial hdac_stream code was adapted a third time with the same
locking issues. Move the spin_lock outside the loops and make sure the
fields are protected on read/write.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210924192417.169243-5-pierre-louis.bossart@linux.intel.comSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/soc/sof/intel/hda-dai.c

@@ -68,6 +68,7 @@ static struct hdac_ext_stream *
 		return NULL;
 	}
 
+	spin_lock_irq(&bus->reg_lock);
 	list_for_each_entry(stream, &bus->stream_list, list) {
 		struct hdac_ext_stream *hstream =
 			stream_to_hdac_ext_stream(stream);
@@ -107,12 +108,12 @@ static struct hdac_ext_stream *
 		 * is updated in snd_hdac_ext_stream_decouple().
 		 */
 		if (!res->decoupled)
-			snd_hdac_ext_stream_decouple(bus, res, true);
-		spin_lock_irq(&bus->reg_lock);
+			snd_hdac_ext_stream_decouple_locked(bus, res, true);
+
 		res->link_locked = 1;
 		res->link_substream = substream;
-		spin_unlock_irq(&bus->reg_lock);
 	}
+	spin_unlock_irq(&bus->reg_lock);
 
 	return res;
 }