remove code made dead in 84556b11

After this commit, the replay_controller constructs
tod_manager_start_ using the same parameters as the play_controller
constructs tod_manager_. So the copy construction after this is
superfluous.

https://github.com/wesnoth/wesnoth/commit/84556b11
Merge branch 'master' of git://github.com/wesnoth/wesnoth