(well_known_*_sid): Change type to cygpsid.
(cygsid::init): Delete declaration.
* sec_helper.cc (well_known_*_sid): Define using above SID macro.
(cygsid::init): Delete.
* dcrt0.cc (dll_crt0_0): Do not call cygsid::init.
* security.cc (get_user_local_groups): Change the second argument type
to cygpsid.