* keyboard.c (init_kboard): Now static. Add arg

* keyboard.c (init_kboard): Now static.  Add arg
to denote window system.  Adjust comment.
(init_keyboard): Adjust user.
(allocate_kboard): New function.
(syms_of_keyboard):
* nsterm.m (ns_term_init):
* term.c (init_tty):
* w32term.c (w32_create_terminal):
* xterm.c (x_term_init): Use it.
* keyboard.h (init_kboard): Remove prototype.
(allocate_kboard): Add prototype.