s3:utils:net: Print debug message about Netbios

s3:utils:net: Print debug message about Netbios

With a preceding patch, cli_connect_nb() will return
NT_STATUS_NOT_SUPPORTED when 'disable netbios' is set in smb.conf.

Print an informative error message to indicate Netbios is disabled
if this occurs.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=13727

Signed-off-by: Justin Stephenson <jstephen@redhat.com>
Reviewed-by: Noel Power <nopower@suse.com>
Reviewed-by: Jeremy Allison <jra@samba.org>
Autobuild-User(master): Noel Power <npower@samba.org>
Autobuild-Date(master): Wed Jan  9 22:38:21 CET 2019 on sn-devel-144