games/tomenet: link to libncurses instead of libcurses
Libcurses is just symlinked to libncurses on FreeBSD base, but it
doesn't exist in ports ncurses.
Approved by: infrastructure blanket (related to ncurses work)
TomeNET is an online multiplayer rogue-like role-playing game,
derived from MAngband (Multiplayer-Angband).
TomeNET loosely bases on the stories of J.R.R. Tolkien mainly
"The Lord Of The Rings", hence the name "the Troubles of Middle
Earth" or alternatively "the Tales of Middle Earth".
Note: only the curses interface is available with this port.
Adding support for graphical interface using X11 is not planned
for now on because I could not easily test it.