ALSA: hda/hdmi: Consider ELD is invalid when no SAD is present
There's a system that reports a bogus HDMI audio interface:
$ cat eld#2.0
monitor_present 1
eld_valid 1
monitor_name
connection_type DisplayPort
eld_version [0x2] CEA-861D or below
edid_version [0x3] CEA-861-B, C or D
manufacture_id 0xe430
product_id 0x690
port_id 0x0
support_hdcp 0
support_ai 0
audio_sync_delay 0
speakers [0xffff] FL/FR LFE FC RL/RR RC FLC/FRC RLC/RRC FLW/FRW FLH/FRH TC FCH
sad_count 0
Since playing audio is not possible without SAD, also consider ELD is
invalid for this case.
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Link: https://lore.kernel.org/r/20211202073338.1384768-1-kai.heng.feng@canonical.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>