Delete orphaned vxlan interface in host namespace

[xinfengliu]

In a highly churned docker swarm cluster, sometimes the error creating vxlan interface: file exists emerges, then it is needed to manually clean up the orphaned vx-xxxxx interfaces in host namespace.

This commit fixes the issue.

Signed-off-by: Xinfeng Liu [email protected]

[xinfengliu]

Hi @thaJeztah , would you mind asking a maintainer to review this PR? Thank you.

[AkihiroSuda]

The repo has moved to https://github.com/moby/moby/tree/master/libnetwork

[corhere]

Closing in favor of https://github.com/moby/moby/pull/42548