Supppress log spam from connection forwarding
Supppress log spam from connection forwarding

- bump the minimal logged threshold to `Info` (was `Debug`)
- avoid logging an error condition which was already logged a few
  lines before

Signed-off-by: David Scott <63c9eb0ea83039690fefa11afe17873ba8278a56@docker.com>

djs55/vpnkit,djs55/vpnkit,djs55/vpnkit