ipa-otpd: handle LDAP timeout in a better way
    
    When LDAP server disconnects ipa-otpd client connection due to a
    timeout, ipa-otpd instance would stop and report an issue. This confuses
    systemd service reporting, so for these situations we better to shut
    down gracefully.
    
    Fixes: https://pagure.io/freeipa/issue/6587
    
    Signed-off-by: Alexander Bokovoy <abokovoy@redhat.com>
    Reviewed-By: Rob Crittenden <rcritten@redhat.com>
    Reviewed-By: Simo Sorce <ssorce@redhat.com>