LU-1856 build: fix 'out-of-bounds write' errors

LU-1856 build: fix 'out-of-bounds write' errors

Fix 'out-of-bounds write' defects found by Coverity version 6.0.3:
Out-of-bounds write (OVERRUN_DYNAMIC or OVERRUN_STATIC)
Overrunning array at too high offset.

Signed-off-by: Sebastien Buisson <sebastien.buisson@bull.net>
Change-Id: Idb2ed5f814bb0c4c9418cedffb8e01efae0f4bd7
Reviewed-on: http://review.whamcloud.com/3903
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Keith Mannthey <keith@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>