utmp/wtmp/lastlog for 64bit systems with 32bit support

[H. J. Lu]

I took a look at utmp/wtmp/lastlog. I think utmp/wtmp should be OK
or easy to fix since there are access functions for them. lastlog
is a problem since there are no access functions. Program will
access lastlog directly. Should we add some access functions for
lastlog?

It looks like a nasty issue on ia64. If we fix the 32bit support,
we have to recompile those programs which access lastlog. If most
of programs which access utmp/wtmp via access functions also access
lastlog directly, it won't make much senses to provide old verioned
access functions for utmp/wtmp since they still won't work right
without rebuild.


H.J.