drm/edid: parse display info has_audio similar to is_hdmi

Since we already iterate everything that's needed for determining audio,
reduce the need to call drm_detect_monitor_audio() by storing has_audio
to connector info.

Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/391a93b25c6bcbb39854aaa2813570cfb1580ed9.1685437500.git.jani.nikula@intel.com