lxc: check actual type of interface not config type

lxc: check actual type of interface not config type

virLXCControllerGetNICIndexes() was deciding whether or not to add the
ifindex for an interface's ifname to the list of ifindexes sent to
CreateMachineWithNetwork based on the interface type stored in the
config. This would be incorrect in the case of <interface
type='network'> where the network was giving out macvlan interfaces
tied to a physical device (i.e. when the actual interface type was
"direct").

Instead of checking the setting of "net->type", we should be checking
the setting of virDomainNetGetActualType(net).

I don't think this caused any actual misbehavior, it was just
technically wrong.

Signed-off-by: Laine Stump <laine@laine.org>
Reviewed-by: Ján Tomko <jtomko@redhat.com>