GeoFlickr example does not ask for permissions on Android

After QTBUG-103478 was fixed, we no longer explicitly request the location permissions when PositionSource is created.

Instead, we do it only when we start requesting position updates. That makes sense in general.

However, GeoFlickr example uses a bit different logic. It checks supportedPositioningMethods before starting updates. And if there are no available positioning methods, it tries to switch to simulation mode (which is currently broken because of QTBUG-105551).

After QTBUG-103478 is fixed, supportedPositioningMethods() always return nothing for a newly-constructed PositionSource, even if Location is enabled on Android.

Adding an implicit permissions request to supportedPositioningMethods() call does not look like a correct approach, because that would be basically similar to what we have fixed in QTBUG-103478.

So we need to find a way to rewrite GeoFlickr example...