ucm2: Qualcomm: document existing hardware

ucm2: Qualcomm: document existing hardware

In most cases its not the config name (device model name) that matters
but the hardware variation of that model. To make currently supported
devices easier to re-use, document the layout. While most configs do
not yet have DP/HDMI defined, it will matter once these are getting
added.

Closes: https://github.com/alsa-project/alsa-ucm-conf/pull/587
Signed-off-by: Aleksandrs Vinarskis <alex@vinarskis.com>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>