webadmin: Show non-overridden QoS values for host interface

Previously only overridden values would be shown - this fetches the
QoS values even if they're configured on the network instead of the
interface (and there's no overriding on the interface).

Change-Id: I74331880697e86dd4764cbdf7cbecaa5210612d8
Signed-off-by: Lior Vernia <lvernia@redhat.com>