LU-17692 flock: get extra reference for lockd

LU-17692 flock: get extra reference for lockd

We should get local locking first for GETLK. Else
the lock_owner could be released while working with
lockd.

Signed-off-by: Yang Sheng <ys@whamcloud.com>
Change-Id: I56e4204e315c2bdbc496b7961519ae45ab1820fe
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/54622
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Lai Siyao <lai.siyao@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>