ASoC: qdsp6: q6asm-dai: checking NULL vs IS_ERR()

The q6asm_audio_client_alloc() doesn't return NULL, it returns error
pointers.

Fixes: 2a9e92d3 ("ASoC: qdsp6: q6asm: Add q6asm dai driver")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

sound/soc/qcom/qdsp6/q6asm-dai.c

@@ -318,10 +318,11 @@ static int q6asm_dai_open(struct snd_pcm_substream *substream)
 	prtd->audio_client = q6asm_audio_client_alloc(dev,
 				(q6asm_cb)event_handler, prtd, stream_id,
 				LEGACY_PCM_MODE);
-	if (!prtd->audio_client) {
+	if (IS_ERR(prtd->audio_client)) {
 		pr_info("%s: Could not allocate memory\n", __func__);
+		ret = PTR_ERR(prtd->audio_client);
 		kfree(prtd);
-		return -ENOMEM;
+		return ret;
 	}
 
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)