Revert "513019 nsslapd-lookthroughlimit is not respected"
This reverts commit 1e3138f1d41562d6f42a8fdf0934af23219bb8e1.
Misunderstood nsslapd-lookthroughlimit. Regardless of the filter test result,
once hit the lookthroughlimit, search should be aborted there. That's what
the original code does and that is correct.