conf: Add card config for Intel HDMI/DP LPE audio

It's a playback-only device with a single PCM dedicated for HDMI/DP
output.  The dmix is working with the latest driver code, so enable it
for default, while providing the hdmi PCM dev for the accesses with
AES bits.

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