LU-15220 lipe: avoid gcc-11 -Werror=stringop-truncation warning

LU-15220 lipe: avoid gcc-11 -Werror=stringop-truncation warning

This patch fixes -Werror=stringop-truncation warnings
in lipe codes.

Test-Parameters: trivial testlist=sanity-lipe

Change-Id: Ie007083b1fe94d81e3772d7c0947457d2c3042ac
Signed-off-by: Jian Yu <yujian@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/47510
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: John L. Hammond <jhammond@whamcloud.com>