Unrevert the 'revert the "talk to netlink directly" change.'

http://ag/486277 was reverted in http://ag/491263 and is being unreverted in
this change. The bug in the original CL was a typo ("interface" instead of the
desired "ifindex"), which is now fixed.

Bug: 15840054
Change-Id: If66987c74cc86e9ba4f7a35d36f0a39afe939a68
1 file changed
tree: 8dce9aefe6096bca426d693135c9bf21065e6df3
  1. client/
  2. include/
  3. server/