smbd/notify: add option "honor change notify privilege"

smbd/notify: add option "honor change notify privilege"

This option can be used to make use of the change notify privilege.
By default notify results are not checked against the file system
permissions.

If "honor change notify privilege" is enabled, a user will only
receive notify results, if he has change notify privilege or sufficient
file system permissions. If a user has the change notify privilege, he
will receive all requested notify results, even if the user does not
have the permissions on the file system.

Pair-Programmed-With: Stefan Metzmacher <metze@samba.org>

Signed-off-by: Björn Baumbach <bb@sernet.de>
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
Autobuild-User(master): Stefan Metzmacher <metze@samba.org>
Autobuild-Date(master): Thu Dec 17 15:01:53 UTC 2020 on sn-devel-184