In a multi-wan setup, netifd may need guidance on which wan device to
use to create the route to the remote peer.
This commit adds a 'tunlink' option similar to other tunneling interfaces
such as 6in4, 6rd, gre, etc.
Signed-off-by: Aaron Goodman <aaronjg@stanford.edu>
Signed-off-by: maurerr <mariusd84@gmail.com>
df050aa3fc