Cleanup host discovery

[aiordache]

Signed-off-by: Anca Iordache anca.iordache@docker.com
relates to moby/moby#40383

[eunomie]

One more occurrence of github.com/docker/docker/pkg/discovery needs to be removed

$ ack pkg/discovery vendor/github.com/docker/libnetwork/
vendor/github.com/docker/libnetwork/config/config.go
8:      "github.com/docker/docker/pkg/discovery"

[arkodg]

will review this once the moby counterpart PR is green since most swarm tests are present there

[thaJeztah]

Thanks for looking into this; so I'd be interested to see if we still require libkv (and if we could get rid of the dependencies for external k/v stores). I see boltdb is also used through the k/v store (and think we still use that, but not sure 😓). Here's a quick attempt to see what happens if we remove some of the code related to external k/v drivers; #2521

[cpuguy83]

Note we have migrated this codebase over to github.com/moby/moby/libnetwork.
We are not accepting PR's on this repo anymore except for backports to be included in moby 20.10

[thaJeztah]

closing this one; this has been merged in moby through moby/moby#42247