ucm-config: remove Dell-WD15-Dock

ALSA lib upstream now maintains ucm files for this dock, lets upstream
what we have and carry any local patches we have to on top of ALSA lib.
This will also allow us to uprev ALSA since currently adhd conflicts
with it.

Added README explaining reasoning behind leaving dead symlinks in the
repo versus adding them to the overlay.

BUG=b:132848755
TEST=emerge and don't conflict with ALSA 1.1.8

Cq-Depend: chromium:1658664
Change-Id: I31f5a52f37e0cafd983249619074ca8f04c27d5d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/adhd/+/1657029
Reviewed-by: Curtis Malainey <cujomalainey@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>
Tested-by: Curtis Malainey <cujomalainey@chromium.org>
Commit-Queue: Jason Clinton <jclinton@chromium.org>
3 files changed