UPSTREAM: drm/i915/xe3lpd: Map POWER_DOMAIN_AUDIO_PLAYBACK to DC_off

In Xe3_LPD, display audio has the core audio logic located in PG0 and
per-transcoder logic in the same power well that provides power for the
transcoder [1].

For stuff like audio device enumeration, we need to ensure that PG0 is
turned on. For playback, we additionally need the transcoder's power
well to be enabled.

That essentially means that, for audio playback, there isn't a special
power well that needs to be enabled, because modeset sequences will
ensure that the required power wells are enabled.

That said, there might be cases where PG0 could be disabled due to
display entering DC6 while the audio driver tries to interact with the
graphics driver for stuff like audio device enumeration.

We recently hit that kind of scenario, where "aplay -l" was being used
to enumerate audio devices on a PTL machine with PSR enabled and no
external displays attached.

Since intel_audio_component_get_power() uses
POWER_DOMAIN_AUDIO_PLAYBACK, make sure to map that power domain to
DC_off power well, so that we disable dynamic DC states (which includes
DC6) while the audio driver needs display audio power.

[1] The core-audio vs per-transcoder logic split is not really new in
    Xe3_LPD. This is also true for previous display generations. We need
    to figure out the correct version where this split happened so that
    we can apply fixes in the current power domain mapping.

Bug: 424451528
Test: Boot to UI on ocelot
(cherry picked from commit eb4796d8)

Bspec: 72519
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250227-xe3lpd-power-domain-audio-playback-v1-1-5765f21da977@intel.com


Change-Id: I7b7d0262f21528835784c01ba5bb976363ff84be
Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
Signed-off-by: FNU VISHWANATHA <fnu.vishwanatha@intel.corp-partner.google.com>