projects: delete scarlet

Bit-rotted, and far from compiling sadly.

It'll always be in the git history if we want to resurrect it someday
for some reason.

BUG=b:177003034
TEST=CQ

Change-Id: If0369980f33ef3baca519504f5dbd7638272cc5d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/zephyr-chrome/+/2634347
Tested-by: Jack Rosenthal <jrosenth@chromium.org>
Auto-Submit: Jack Rosenthal <jrosenth@chromium.org>
Commit-Queue: Paul Fagerburg <pfagerburg@chromium.org>
Reviewed-by: Paul Fagerburg <pfagerburg@chromium.org>
12 files changed