ALSA: hda: Fix null-ptr-deref when i915 fails and hdmi is denylisted

ALSA: hda: Fix null-ptr-deref when i915 fails and hdmi is denylisted

If snd_hda_hdmi_codec module is denylisted and any event causes i915
enumeration to fail, is_likely_hdmi_codec() ends in null-ptr-deref.

As snd_soc_hda is an ASoC-based driver, its initialization is delayed
until all the necessary components appear in the system - allowing
actual sound card to enumerate. snd_hda_codec_configure() gets called by
the avs-driver core during probe_codecs() but the
snd_hda_codec_device_new(), necessary to complete codecs initialization,
happens only when codec-component of hda sound card is being probed.

Denylisting snd_hda_codec_hdmi module causes snd_hda_codec_configure()
to reach: codec_bind_generic() -> is_likely_hdmi_codec() which makes use
of ->wcaps and at this point the it isn't initialized yet - again,
requires completion of snd_hda_codec_device_new().

Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Link: https://lore.kernel.org/r/20220706120230.427296-3-cezary.rojewski@intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>