ldb: binding ordered indexes to GUID indexing

ldb: binding ordered indexes to GUID indexing

To reduce the number of potential combinations of database features in
ldb, we want to link all new database features since 4.7. GUID indexing,
ordered integers, and pack format changes will all upgrade together.
This patch makes ordered integers only function if GUID indexing is
enabled. If GUID indexing is disabled, ORDERED_INTEGER will not be
written to @ATTRIBUTES and a syntax's index_format_fn will never be
used.

Signed-off-by: Aaron Haslett <aaronhaslett@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Garming Sam <garming@catalyst.net.nz>