drm/i915/audio: migrate away from kdev_to_i915()

drm/i915/audio: migrate away from kdev_to_i915()

Use to_intel_display() instead of kdev_to_i915() in the audio component
API hooks. Avoid further drive-by changes at this point, and just
convert the display pointer to i915, and leave the struct intel_display
conversion for later.

Reviewed-by: Gustavo Sousa <gustavo.sousa@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/35ef00470db0088eb82b0406e4f7730154f54baf.1724942754.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>