Re: parallel bootstrap failure; _prompt_? during bootstrap build

[Richard Stallman <rms@gnu.org>]

	      ;; XXX This was disabled unless `window-system', but that
	      ;; leads to buggy behaviour when a tty frame is opened
	      ;; later.  Setting the keyboard coding system has no adverse
	      ;; effect on X, so let's do it anyway. -- Lorentey

There's one adverse effect: it loads encoded-kb.
We could either preload encoded-kb, or make a change to
do this the first time a tty is opened.

I prefer the latter since most sessions don't use a tty.