* service/rpccommon: log error for conns rejected by --only-same-user
If no logger is enabled manually write to stderr instead.
Fixes#2209
* logflags: fix style complaints from DeepSource
* service: also search IPv6 connections when checking user
When checking if the user is allowed to connect to this Delve instance
also search IPv6 connections even though the local address is IPv4.
Fixes#1835
* cmd: add flag to disable same-user check
Fixes#1835
This prevents other users on the same machine (e.g. a production server) from
using dlv under the credentials of another user, which poses a security issue.