_KMEMUSER and __HAVE_CPU_DATA_FIRST

[Frank Wille <frank%phoenix.owl.de@localhost>]

Hi!

A few days ago I learned from Christos that the MI part of cpu_info, i.e.
ci_data, should be exposed when _KMEMUSER is defined, to make vmstat
compile again.

An alternative would have been when "struct cpu_data ci_info" was the first
entry in all cpu_info structures.

Then I saw Matt's last changes, which defined __HAVE_CPU_DATA_FIRST for
nearly any port, which seems to be like this is exactly what was needed?

Now I ask myself: could we use __HAVE_CPU_DATA_FIRST somehow as an
alternative for _KMEMUSER? Or do we want to change each <cpu>/include/cpu.h
to expose cpu_info when _KMEMUSER is defined?

I already tried to fix powerpc/include/cpu.h, but it seems that all ports
are affected...? Probably I'm just confused and missing some information?
;)

-- 
Frank Wille