LU-16000 utils: align updatelog parameters in llog_reader

LU-16000 utils: align updatelog parameters in llog_reader

Parameters in update log records are aligned on 64bits. llog_reader
do not aligned these parameters: if a parameters size is not mutiple
of 8, the next parameter size will be read incorrectly.

Test-Parameters: trivial
Fixes: 9962d6f ("LU-14617 utils: llog_reader updatelog support")
Signed-off-by: Etienne AUJAMES <eaujames@ddn.com>
Change-Id: I6871614ab4ea79d59c3c3b4644b377de395bad56
Reviewed-on: https://review.whamcloud.com/47913
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Alexander Boyko <alexander.boyko@hpe.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Mike Pershin <mpershin@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>