LU-17572 lov: remove noise from lov_init_sub()

LU-17572 lov: remove noise from lov_init_sub()

lov_init_sub() generates too many messages in applications like racer.
let's make it a bit less noisy.

Test-Parameters: trivial
Signed-off-by: Alex Zhuravlev <bzzz@whamcloud.com>
Change-Id: I00ae75597b550c29122d8fb9d34d4e0d24c38dd5
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/54125
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>