meta-uhmi: propagate the app_id to UHMI FW nodes

meta-uhmi: propagate the app_id to UHMI FW nodes

To support gRPC for UHMI, rvgpu-renderer must register the app_id with
agl-compositor, and uhmi-agl-wm must use it to run gRPC commands.

After this commit, please set the same app_id to Json files below:
* app.json: set "app_id" key under "backend_params"
* initial_vscreen.json: set "APPID" key under "vsurface"
Then, the app_id is propagated from ula to uhmi-agl-wm and from ucl
to remote-virtio-gpu and gRPC can change layouts of apps.

Bug-AGL: SPEC-5356

Change-Id: Ie835b794f30b199675ff8901d551854ff721ebc8
Signed-off-by: Kenta <murakami.kenta002@jp.panasonic.com>