ssh_host_key_file default in help and sample don't match the actual default

[Mark Sturdevant]

The commit message and the actual default say the default value for ssh_host_key_file is $state_path/ssh_known_hosts, but the config.conf.sample and the config opts help say it is "$state_path/known_hosts".

Fix the help and config.conf.sample to match the actual default.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/123335
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=49ddd125a37e50cc2afe1ebecacac1a34742f478
Submitter: Jenkins
Branch: master

commit 49ddd125a37e50cc2afe1ebecacac1a34742f478
Author: Mark Sturdevant <email address hidden>
Date: Mon Sep 22 22:45:14 2014 -0700

    Fix ssh_host_key_file default in help and config.sample.conf

    The commit message and the actual default say the default value for
    ssh_host_key_file is $state_path/ssh_known_hosts, but the
    config.conf.sample and the config opts help say it is
    "$state_path/known_hosts".

    Fix the help and config.conf.sample to match the actual default.

    Closes-Bug: 1372765
    Change-Id: I51a2918155a27afcf48eda01f32774ce0d346d06