LU-4055 build: fix 'error handling' issues

LU-4055 build: fix 'error handling' issues

Fix 'error handling' issues found by Coverity version 6.6.1:
Unchecked return value (CHECKED_RETURN)
Calling function without checking return value.
Argument cannot be negative (NEGATIVE_RETURNS)
Negative value used as argument to a function expecting a
positive value.

Signed-off-by: Sebastien Buisson <sebastien.buisson@bull.net>
Change-Id: I1ea3428febee741be15215fcc89266a814e5fe1b
Reviewed-on: http://review.whamcloud.com/7842
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: James Nunez <james.a.nunez@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>