kern: console: make /dev/console backing console more predictable
Specifically, altering the console list with conscontrol has some weird
behavior:
- If you remove the first configured console, /dev/console will become unconfigured
- Any console added becomes the /dev/console
In a multicons situation, #1 is clearly a bug and #2 is perhaps slightly
less clear. If we have ttyu0, ttyv0, then it seems obvious that one
would want ttyv0 to take over the console if ttyu0 is removed. If we
add ttyu0 back in, then it's debatable whether it should take over the
console or not.
Fix it now to make the /dev/console selection more FIFO-ish, with
respect to how conscontrol affects it. A primary verb for
conscontrol(8) might be a good addition.