libmultipath: finally fix dev_loss_tmo setting

A 'no_path_retry' setting of '0' (or 'fail') and a
non-zero fast_io_fail_tmo setting would cause the
dev_loss_tmo setting to become '0'.
As this was an invalid value the lpfc driver would
silently modify it to '1'.

References: bnc#889927

Signed-off-by: Hannes Reinecke <hare@suse.de>
- Update Changelog