ASoC: SOF: Intel: Initialize hdaudio bus properly

The SOF HD-audio bus has its house-made initialization code.  It's
supposedly for making the code independent from HD-audio bus drivers.
However, this is error-prone, and above all, the SOF driver has
already dependency on HD-audio bus driver when CONFIG_SND_SOF_HDA is
set.  That is, if this Kconfig is set, there is no reason to avoid the
call to the proper bus init function.

Also, the ext_ops that is set at bus initialization can be better
handled inside sof_hda_bus_init().  We don't need to refer this
outside the bus initialization.

So this patch addresses these issues:
- sof_hda_bus_init() calls nothing but snd_hdac_ext_bus_init()
  when CONFIG_SND_SOF_HDA is set.  Otherwise some fields are
  initialized locally like before for avoiding the dependency.
- ext_ops is referred inside sof_hda_bus_init().  The ext_ops argument
  of snd_hda_bus_init() is dropped.

Acked-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/soc/sof/intel/hda.c

@@ -236,7 +236,6 @@ static int hda_init(struct snd_sof_dev *sdev)
 {
 	struct hda_bus *hbus;
 	struct hdac_bus *bus;
-	struct hdac_ext_bus_ops *ext_ops = NULL;
 	struct pci_dev *pci = to_pci_dev(sdev->dev);
 	int ret;
 
@@ -244,10 +243,7 @@ static int hda_init(struct snd_sof_dev *sdev)
 	bus = sof_to_bus(sdev);
 
 	/* HDA bus init */
-#if IS_ENABLED(CONFIG_SND_SOC_SOF_HDA_AUDIO_CODEC)
-	ext_ops = snd_soc_hdac_hda_get_ops();
-#endif
-	sof_hda_bus_init(bus, &pci->dev, ext_ops);
+	sof_hda_bus_init(bus, &pci->dev);
 
 	/* Workaround for a communication error on CFL (bko#199007) and CNL */
 	if (IS_CFL(pci) || IS_CNL(pci))