Renamed ui_room_member_nick_change -> mucwin_occupant_nick_change

src/event/server_events.c

@@ -628,7 +628,7 @@ sv_ev_muc_occupant_online(const char *const room, const char *const nick, const
     // handle nickname change
     char *old_nick = muc_roster_nick_change_complete(room, nick);
     if (old_nick) {
-        ui_room_member_nick_change(room, old_nick, nick);
+        mucwin_occupant_nick_change(room, old_nick, nick);
         free(old_nick);
         occupantswin_occupants(room);
         return;