Move DNS options to hostconfig

The local resolver warning needed to be moved at daemon start because it
was only show for the first container started anyways before having a
default value set.
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
Merge pull request #5066 from crosbymichael/remove-dns-conf

Move DNS options to hostconfig