ldb-samba: Implement transitive extended matching

ldb-samba: Implement transitive extended matching

Documented in [MS-ADTS] section 3.1.1.3.4.4.3 LDAP_MATCHING_RULE_TRANSITIVE_EVAL

This allows a search filter such as:

 member:1.2.840.113556.1.4.1941:=cn=user,cn=users,dc=samba,dc=example,dc=com

This searches not only the member attribute, but also any member
attributes that point at an object with this member in them.  All the
various DN syntax types are supported, not just plain DNs.

Signed-off-by: Samuel Cabrero <samuelcabrero@kernevil.me>
(abartlet: Fixed compile error: return makes integer from pointer without a cast)
Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Garming Sam <garming@catalyst.net.nz>