ALSA: hda - Get rid of AMD HDMI exception in hdmi_present_sense()

Since the recent fake ELD patches, we can remove the check for AMD
HDMI in hdmi_present_sense() and decide the return value from
eld_valid value.

Suggested by Anssi Hannula.

Signed-off-by: Takashi Iwai <tiwai@suse.de>