We don't need to crash hard here, it's just reading a sysfs file. The
values considered in switch are from a fixed set, the default case
should not happen at all.
Signed-off-by: David Sterba <dsterba@suse.cz> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>