Drop unused `circuit_dump_by_chan` function

Well, it's unused. Noticed when working on legacy/trac#4519 (moved).

Trac:
Username: marek

changed milestone to %Tor: 0.2.5.x-final in legacy/trac

added 025-triaged in Legacy / Trac component::core tor/tor in Legacy / Trac milestone::Tor: 0.2.5.x-final in Legacy / Trac priority::very low in Legacy / Trac reporter::marek in Legacy / Trac resolution::implemented in Legacy / Trac status::closed in Legacy / Trac tor-relay in Legacy / Trac type::enhancement in Legacy / Trac labels

Trac:
Username: marek

0001-Remove-unused-function-circuit_dump_by_chan-Fix-9107.patch

Trac:
Username: marek

Trac:
Username: marek
Status: new to needs_review

Trac:
Username: marek

0002-Also-remove-definition-from-the-header.patch

Trac:
Username: marek

I think that this function got added by Andrea with the plan that it could be useful for debugging. Not sure whether it is something to keep though. Andrea, what do you think?

Trac:
Milestone: N/A to Tor: 0.2.5.x-final
Keywords: N/A deleted, tor-relay added
Cc: N/A to andrea

Andrea says this function is okay to kill. I should merge this in 0.2.5.4-alpha.

Trac:
Keywords: tor-relay deleted, tor-relay 025-triaged added

Merged!

Trac:
Resolution: N/A to implemented
Status: needs_review to closed

closed

moved from legacy/trac#9107 (moved)

added Feature label and removed 1 deleted label

added Relay label and removed 1 deleted label