agl-uhmi: Add two build target for UHMI

agl-uhmi: Add two build target for UHMI

This adds two new target builds agl-uhmi-demo-preconfigured-receiver-agl
and agl-uhmi-demo-preconfigured-sender-agl which pulls in the AGL
compositor, native-agl-shell and packagegroup-ddfw-agl.

packagegroup-ddfw-agl is a new package being added here that adds in and
pulls uhmi-agl-wm (the window managent configuration layout for the
AGL compositor).

Bug-AGL: SPEC-5280
Change-Id: I481c1648a62be83ee853c27a74a1659954b88227
Signed-off-by: Marius Vlad <marius.vlad@collabora.com>