perf build broke by list_head changes...

[David Miller <davem@davemloft.net>]

Commit:

commit de5d9bf6541736dc7ad264d2b5cc99bc1b2ad958
Author: Chris Metcalf <cmetcalf@tilera.com>
Date:   Fri Jul 2 13:41:14 2010 -0400

    Move list types from <linux/list.h> to <linux/types.h>.

broke the build of 'perf'.

If you move "struct list_head" into types.h, this means perf stops
building because it depends upon being able to include linux/list.h
from a userland application and at the same time be able to get the
basic data types without defining __KERNEL__ or similar.

Now that no longer occurs because the bulk of types.h is __KERNEL__
protected and thus the build breaks since "struct list_head" is
never defined.