SSS_CACHE: Allow sss_cache tool to flush SSH hosts cache
Resolves:
https://fedorahosted.org/sssd/ticket/2358
Signed-off-by: Jan Cholasta <jcholast@redhat.com>
Reviewed-by: Jan Cholasta <jcholast@redhat.com>
Reviewed-by: Pavel Reichl <preichl@redhat.com>