avg 8f560f2f98 boot/console: handle consoles that fail to probe
- clarify meaning of console flags
- perform i/o via a console only if both of the following conditions are met:
   o console is active (selected by user or config)
   o console flags that it can perform the operation
- warn if a chosen console can not work (the warning may go nowhere without
  working and active console, though)

Reviewed by:	jhb
Tested by:	Uffe Jakobsen <uffe@uffe.org>,
		Olivier Cochard-Labbe' <olivier@cochard.me>
MFC after:	26 days
2012-10-06 20:01:17 +00:00
..
2011-05-07 13:57:30 +00:00
2012-09-30 13:17:33 +00:00
2011-02-27 12:25:47 +00:00