EC2 instances don't have a console, so it's pointless to start
emergency mode if a mount fails. (This happened to me with an
encrypted filesystem where the key wasn't sent on time using "charon
send-keys".) Better to cross fingers and continue booting.
problem in stage 1 should cause a panic. (Actually, the latter
should probably kill the instance since we can't repair it
anyway...)
svn path=/nixos/trunk/; revision=30215