The example mostly shows the usage of
QBluetooth{Device,Service}DiscoveryAgent classes, which is also
illustrated by other examples. Move it, because it's not fully
functional on mobile platforms (because it's widget based).
Do not remove it completely, because it might still be useful
for doing Classic device scan.
Also implement some improvements while on it:
* fix CMakeLists.txt by using qt_standard_project_setup() and PRIVATE
linking
* fix memory leak in DeviceDiscoveryDialog
* rework the code to use Qt parent-child model instead of manually
deleting objects where possible
* fix includes
* fix forward declarations
Task-number: QTBUG-111972
Pick-to: 6.5 6.5.0
Change-Id: Ie4bc9e25ccdda6d5f5de2f57528df349c71cdc12
Reviewed-by: Juha Vuolle <juha.vuolle@qt.io>
Ivan Solovev