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

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

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

Change-Id: I4ca764f359605a452cf4934e6a93106e91d2cc32
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-on: https://review.whamcloud.com/25384
Reviewed-by: Fan Yong <fan.yong@intel.com>
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>