LU-8843 client: fix all less than 0 comparison for unsigned values

LU-8843 client: fix all less than 0 comparison for unsigned values

Remove all test of less than zero for unsigned values
found with -Wtype-limits.

Change-Id: Ia0a5cc5fc280b3856397cc8a494014368a04bf75
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-on: https://review.whamcloud.com/23811
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Jian Yu <jian.yu@intel.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>