ASoC: mediatek: mt8365: check validity before usage of i2s_data

There may be a case where i2s_data may not get initialized by the for
loop which will cause the kernel crash. Initialize the i2s_data to NULL
and abort execute if it isn't found.

Fixes: 402bbb13a195 ("ASoC: mediatek: mt8365: Add I2S DAI support")
Signed-off-by: Muhammad Usama Anjum <[e-mail]>
Reviewed-by: AngeloGioacchino Del Regno <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/mediatek/mt8365/mt8365-dai-i2s.c

···
 	int i;
 	unsigned long flags;
 	struct mt8365_afe_private *afe_priv = afe->platform_priv;
-	struct mtk_afe_i2s_priv *i2s_data;
+	struct mtk_afe_i2s_priv *i2s_data = NULL;
 
 	for (i = 0; i < DAI_I2S_NUM; i++) {
 		if (mt8365_i2s_priv[i].adda_link)
 			i2s_data = afe_priv->dai_priv[mt8365_i2s_priv[i].id];
 	}
+
+	if (!i2s_data)
+		return;
 
 	spin_lock_irqsave(&afe_priv->afe_ctrl_lock, flags);