Re-enable /dev/console
Re-enable /dev/console

This re-enables a pts device backing /dev/console and allows container
writes to it.

That change will break CRIU until it knows how to deal with
/dev/console, but lakc of /dev/console is breaking enough workloads that
it's the best option for now.

Closes #1463

Signed-off-by: Stéphane Graber <089afc6d81f66f1168a9849e15660feae286e024@ubuntu.com>

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