smbd: use fsp->conn->session_info for the initial delete-on-close token

smbd: use fsp->conn->session_info for the initial delete-on-close token

There's a correctly set up session_info at fsp->conn->session_info, we can just
use that.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14617

Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Tue Jan 26 04:04:14 UTC 2021 on sn-devel-184

(cherry picked from commit e06f86bbd93d024c70016e1adcf833db85742aca)

Autobuild-User(v4-13-test): Karolin Seeger <kseeger@samba.org>
Autobuild-Date(v4-13-test): Mon Feb  1 08:47:05 UTC 2021 on sn-devel-184