LU-17347 debs: also move .ddeb files into debs/

LU-17347 debs: also move .ddeb files into debs/

When building debian packages, the resulting packages are
moved into a 'debs/' subdir.

Don't miss the debug symbol packages 'dbgsym', which are
suffixed .ddeb.

Also add .buildinfo file.

Lustre-change: https://review.whamcloud.com/53378/
Lustre-commit: TBD

Test-Parameters: trivial
Change-Id: I52d0bddfaafc67c4a2a2dbc786d7f320c0b979f8
Signed-off-by: Aurelien Degremont <adegremont@nvidia.com>
Signed-off-by: Minh Diep <mdiep@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/53421
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Jian Yu <yujian@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>