LU-9019 llite: change lli_glimpse_time to ktime

LU-9019 llite: change lli_glimpse_time to ktime

Currently lli_glimpse_time is in jiffies which can vary between
platforms. Migrate to ktime since we need more than second
time resolution that is consistent on any platform. Replace the
last cfs_time_current_sec() with ktime_get_real_seconds().

Change-Id: I352c3adbd07d9dadb7e5dbe180447a1cb18a48d2
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-on: https://review.whamcloud.com/30601
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: Mike Pershin <mike.pershin@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>