Incomplete slapi_int_ldapmods2modifications() change

[Hallvard B Furuseth <h.b.furuseth@usit.uio.no>]

slapi/slapi_utils.c rev 1.172 removed the 'dup' parameter to
slapi_int_ldapmods2modifications(), but a 'dup' test remains in the
function body.  (It evaluates to the address of the function dup().)

> Add slapi_dn_isbesuffix()
> Fix slapi_dn_beparent() logic
> Fix slapi_int_ldapmods2modifications() memory management, values
> always need to be duplicated because of prettying in slap_mods_check()

-- 
Hallvard