QtIFW

Fix addDependency functionality

addDependency was acting weird - if a subcomponent was added as
dependency, the parent was not installed. It was installed the next time
the installer was launched and something else was added/removed.
addDependency should behave the same as when selecting the component
from UI - it should install the parents too

Task-number: QTIFW-1458
Change-Id: I21726ad6acda3b1fb382263405754c2d682dea76
Reviewed-by: Iikka Eklund <iikka.eklund@qt.io>