QtIFW

Remove unneeded member holding virtual children

Virtual children always lie after the
non-virtual ones inside allChildren list anyway.

Change-Id: Iefccabfc1d15f41a7e211b8fe4f518d1948013b1
Reviewed-by: Niels Weber <niels.weber@theqtcompany.com>
Reviewed-by: Kai Koehne <kai.koehne@theqtcompany.com>