Rikku: Add the servo overlay for Rikku

Rikku is a Jecht clone and references the Jecht overlay.

BUG=none
TEST=run 'cros_workon --host start hdctools'
         'sudo emerge hdctools'
         'sudo servod --board=rikku'

Change-Id: I785a43e67a47b39768b41f76518dc7cf918f34b4
Signed-off-by: Ren Kuo <ren.kuo@quantatw.com>
Reviewed-on: https://chromium-review.googlesource.com/242736
Reviewed-by: Shawn N <shawnn@chromium.org>
Commit-Queue: David Wu <david_wu@quantatw.com>
2 files changed