LU-19099 llite: Add vfstrace debug prints for ll_fallocate

LU-19099 llite: Add vfstrace debug prints for ll_fallocate

Currently ll_fallocate() does not have any vfstrace prints, but
it's important for debugging related issues.

Fixes: 48457868a02a ("LU-3606 fallocate: Implement fallocate preallocate operation")
Test-Parameters: trivial
Change-Id: I165a7208a59b055756db416063c6695cc7f2d8e4
Signed-off-by: Oleg Drokin <green@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/59718
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Reviewed-by: Emoly Liu <emoly@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>