* No need for the atomically changed variables to be declared as
volatile.
* Drop support for atomically getting and setting unaligned data.
* Introduce atomic_get_and_set[64]() which works the same as
atomic_set[64]() used to. atomic_set[64]() does not return the
previous value anymore.
Doesn't do anything ATM, but already provides the required system
interface (VFS, caches, POSIX functions).
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20859 a95241bf-73f2-0310-859d-f6bbb57e9c96