drm/i915: make pipe/port based audio valid accessors easier to use

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --cc drivers/gpu/drm/i915/i915_reg.h
Simple merge

diff --cc drivers/gpu/drm/i915/intel_audio.c
Simple merge

diff --cc drivers/gpu/drm/i915/intel_ddi.c
Simple merge