Trogdor: Initial servod board overlay

Create Trogdor board overlay so we can start servod for debugging and
flashing EC image.

BUG=b:143616352
TEST=sudo servod -b trogdor

Change-Id: Ib56d8227fbd4972df1984ba35509b8b0e7c35d9e
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/hdctools/+/1898612
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Douglas Anderson <dianders@chromium.org>
Commit-Queue: Douglas Anderson <dianders@chromium.org>
diff --git a/servo/servo_interfaces.py b/servo/servo_interfaces.py
index 05492bc..d3348d1 100644
--- a/servo/servo_interfaces.py
+++ b/servo/servo_interfaces.py
@@ -306,6 +306,7 @@
     'sentry',
     'soraka',
     'strago',
+    'trogdor',
     'volteer',
     'zoombini',
     'zork',