s4-dsdb: Schedule SD propegation only after successful rename

s4-dsdb: Schedule SD propegation only after successful rename

This avoids needing to anticipate errors that the rename might give
while allowing the dsdb_find_nc_root() routine to become stricter.

The problem is that dsdb_find_nc_root() will soon do a real search and
so fail more often, but these failures will give "wrong" error codes.

We do not need to do this work if the operation fails, so put this in
the callback.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=10635

Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>