To be able to label incoming tor connections as different from normal localhost connections in e.g. `getpeerinfo` and the peers list in the GUI it'd be useful to have them connect on an alternative local-only port. Or even better, a UNIX socket.

For manually set-up hidden services this would have to be configured manually and could add a `hsport` option or such. The external port would still appear as `XXXXXXXXX.onion:8333`, however internally it would redirect to a that port.

In the case of `torcontrol` this would be easy to set up automatically. It could add a new (localhost) binding port automatically and this code would have to be changed:
- https://github.com/bitcoin/bitcoin/blob/master/src/torcontrol.cpp#L441
- https://github.com/bitcoin/bitcoin/blob/master/src/torcontrol.cpp#L477

#if defined(HAVE_CONFIG_H)
#include <config/bitcoin-config.h>
#endif
#include <init.h>
#include <addrman.h>
#include <amount.h>
#include <banman.h>
#include <blockfilter.h>
#include <chain.h>
#include <chainparams.h>
#include <compat/sanity.h>
#include <consensus/validation.h>
#include <fs.h>
#include <hash.h>
#include <httprpc.h>
#include <httpserver.h>
#include <index/blockfilterindex.h>
#include <index/txindex.h>
#include <interfaces/chain.h>
#include <interfaces/node.h>
#include <key.h>