Avoid "cast pointer to int of different size" warning by passing
the int arg to new threads as an offset into rtid/rwtid.

LDAP_FREE() -> ber_memfree(), msg->lm_ber -> ldap_get_message_ber(msg).

It modified ldap_int_sasl_bind()'s prototype with but not without SASL.

Also rearrange slightly to silence gcc -Wuninitialized, get a single
exit point, and skip the unnecessary sorting of the single value.

do not add hasSubordinates if already present (fixes ITS#6712 for back-bdb/hdb, other backends may need work)

is removed (additional fix for ITS#6647)