Update test/devel feature and crosssdk definitions

To match the update in meta-agl, rework to drop the agl-test-wgt and
agl-devel-wgt feature package additions and now unnecessary test/devel
packagegroups. They'll now be pulled in by the COMPLEMENTARY_GLOBS
definitions for those image features.

As well, to ensure that agl-demo-platform-crosssdk contains required
extra additions, use new .inc file from meta-agl-profile-graphical-qt5
in the SDK definition.

Bug-AGL: SPEC-3300, SPEC-3375

Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: I6b54af5f7c76965171282ed81dc8160c69a9441f