drm/i915: Rename SDVO_AUDIO_ENABLE to HDMI_AUDIO_ENABLE

The "audio enable" bit on the SDVO/HDMI control register is only meant
for HDMI. Audio is never delivered over the SDVO bus. Rename the define
to reflect this fact.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190409144054.24561-4-ville.syrjala@linux.intel.com


Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>