modules: Add the Arduino Zephyr API

Add the Arduino Core API for zephyr as an optional module
However, don't make the group as optional because it will
make it an "inactive project" and so get ignored by west.
This will in turn fail to recognise cmakelists and kconfig
from the module leading to build failures.

Signed-off-by: Dhruva Gole <d-gole@ti.com>

Author: DhruvaG2000

submanifests/optional.yaml

@@ -15,6 +15,10 @@ manifest:
       remote: upstream
       groups:
         - optional
+    - name: gsoc-2022-arduino-core
+      revision: 9e6adb1c0df4ecc059ad6b0f8b4639134d6a1469
+      path: modules/lib/Arduino-Zephyr-API
+      remote: upstream
     - name: lz4
       revision: 8e303c264fc21c2116dc612658003a22e933124d
       path: modules/lib/lz4