LU-9019 osp: migrate to 64 bit time

LU-9019 osp: migrate to 64 bit time

Change opd_statfs_maxage from int to time64_t to make it clear
this field is in units of seconds. Change the last libcfs specific
cfs_time_t which maps to jiffies to ktime_t since it give better
than second resolution which is needed in this case.

Change-Id: I31baa73d5f6bd53dbcce4fc9f90462b11c6457a3
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-on: https://review.whamcloud.com/30674
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>