Unused buttons declared in depot_frame_t

[Ranran]

I was checking the code because I felt the need to update the depot dialog even in extended.
I noticed that there are some button declarations that seem to be no longer in use. I think these may be relics of the past.

These are the buttons below.
bt_destroy, bt_new_line, bt_change_line, bt_apply_line

[prissi]

Thank you, they are gone in r10650