gtk+-2: If gtk fails to initialize, fallback to the curses backend.
* gtk+-2/pinentry-gtk-2.c (main): Use gtk_init_check instead of gtk_init. If gtk_init_check fails, fallback to the curses backend.
issue #1982.
- Reported-by: Daniel Kahn Gillmorr <dkg@fifthhorseman.net>. Closes