ASoC: Intel: hdac_hdmi: Set ops to NULL on remove

[ Upstream commit 0f6ff78540bd1b4df1e0f17806b0ce2e1dff0d78 ]

When we unload Skylake driver we may end up calling
hdac_component_master_unbind(), it uses acomp->audio_ops, which we set
in hdmi_codec_probe(), so we need to set it to NULL in hdmi_codec_remove(),
otherwise we will dereference no longer existing pointer.

Signed-off-by: Amadeusz Sławiński <amadeuszx.slawinski@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

sound/soc/codecs/hdac_hdmi.c

@@ -1854,6 +1854,12 @@ static void hdmi_codec_remove(struct snd_soc_component *component)
 {
 	struct hdac_hdmi_priv *hdmi = snd_soc_component_get_drvdata(component);
 	struct hdac_device *hdev = hdmi->hdev;
+	int ret;
+
+	ret = snd_hdac_acomp_register_notifier(hdev->bus, NULL);
+	if (ret < 0)
+		dev_err(&hdev->dev, "notifier unregister failed: err: %d\n",
+				ret);
 
 	pm_runtime_disable(&hdev->dev);
 }