net: Skip anything but lo and tun in write_ifaddr

Until there will be a proper way to test venet creation,
skip anything but lo and tun addresses.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
net: Zap routes until venet is testable

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>